Built-In Functions

Flink Table API & SQL provides users with a set of built-in functions for data transformations. This page gives a brief overview of them. If a function that you need is not supported yet, you can implement a user-defined function. If you think that the function is general enough, please open a Jira issue for it with a detailed description.

Scalar Functions

The scalar functions take zero, one or more values as the input and return a single value as the result.

Comparison Functions

Comparison functions Description
value1 = value2

Returns TRUE if value1 is equal to value2; returns UNKNOWN if value1 or value2 is NULL.

value1 <> value2

Returns TRUE if value1 is not equal to value2; returns UNKNOWN if value1 or value2 is NULL.

value1 > value2

Returns TRUE if value1 is greater than value2; returns UNKNOWN if value1 or value2 is NULL.

value1 >= value2

Returns TRUE if value1 is greater than or equal to value2; returns UNKNOWN if value1 or value2 is NULL.

value1 < value2

Returns TRUE if value1 is less than value2; returns UNKNOWN if value1 or value2 is NULL.

value1 <= value2

Returns TRUE if value1 is less than or equal to value2; returns UNKNOWN if value1 or value2 is NULL.

value IS NULL

Returns TRUE if value is NULL.

value IS NOT NULL

Returns TRUE if value is not NULL.

value1 IS DISTINCT FROM value2

Returns TRUE if two values are not equal. NULL values are treated as identical here.

E.g., 1 IS DISTINCT FROM NULL returns TRUE; NULL IS DISTINCT FROM NULL returns FALSE.

value1 IS NOT DISTINCT FROM value2

Returns TRUE if two values are equal. NULL values are treated as identical here.

E.g., 1 IS NOT DISTINCT FROM NULL returns FALSE; NULL IS NOT DISTINCT FROM NULL returns TRUE.

value1 BETWEEN [ ASYMMETRIC | SYMMETRIC ] value2 AND value3

By default (or with the ASYMMETRIC keyword), returns TRUE if value1 is greater than or equal to value2 and less than or equal to value3. With the SYMMETRIC keyword, returns TRUE if value1 is inclusively between value2 and value3. When either value2 or value3 is NULL, returns FALSE or UNKNOWN.

E.g., 12 BETWEEN 15 AND 12 returns FALSE; 12 BETWEEN SYMMETRIC 15 AND 12 returns TRUE; 12 BETWEEN 10 AND NULL returns UNKNOWN; 12 BETWEEN NULL AND 10 returns FALSE; 12 BETWEEN SYMMETRIC NULL AND 12 returns UNKNOWN.

value1 NOT BETWEEN [ ASYMMETRIC | SYMMETRIC ] value2 AND value3

By default (or with the ASYMMETRIC keyword), returns TRUE if value1 is less than value2 or greater than value3. With the SYMMETRIC keyword, returns TRUE if value1 is not inclusively between value2 and value3. When either value2 or value3 is NULL, returns TRUE or UNKNOWN.

E.g., 12 NOT BETWEEN 15 AND 12 returns TRUE; 12 NOT BETWEEN SYMMETRIC 15 AND 12 returns FALSE; 12 NOT BETWEEN NULL AND 15 returns UNKNOWN; 12 NOT BETWEEN 15 AND NULL returns TRUE; 12 NOT BETWEEN SYMMETRIC 12 AND NULL returns UNKNOWN.

string1 LIKE string2 [ ESCAPE char ]

Returns TRUE if string1 matches pattern string2; returns UNKNOWN if string1 or string2 is NULL. An escape character can be defined if necessary.

Note: The escape character has not been supported yet.

string1 NOT LIKE string2 [ ESCAPE char ]

Returns TRUE if string1 does not match pattern string2; returns UNKNOWN if string1 or string2 is NULL. An escape character can be defined if necessary.

Note: The escape character has not been supported yet.

string1 SIMILAR TO string2 [ ESCAPE char ]

Returns TRUE if string1 matches SQL regular expression string2; returns UNKNOWN if string1 or string2 is NULL. An escape character can be defined if necessary.

Note: The escape character has not been supported yet.

string1 NOT SIMILAR TO string2 [ ESCAPE char ]

Returns TRUE if string1 does not match SQL regular expression string2; returns UNKNOWN if string1 or string2 is NULL. An escape character can be defined if necessary.

Note: The escape character has not been supported yet.

value1 IN (value2 [, value3]* )

Returns TRUE if value1 exists in the given list (value2, value3, ...). When (value2, value3, ...). contains NULL, returns TRUE if the element can be found and UNKNOWN otherwise. Always returns UNKNOWN if value1 is NULL.

E.g., 4 IN (1, 2, 3) returns FALSE; 1 IN (1, 2, NULL) returns TRUE; 4 IN (1, 2, NULL) returns UNKNOWN.

value1 NOT IN (value2 [, value3]* )

Returns TRUE if value1 does not exist in the given list (value2, value3, ...). When (value2, value3, ...). contains NULL, returns FALSE if value1 can be found and UNKNOWN otherwise. Always returns UNKNOWN if value1 is NULL.

E.g., 4 NOT IN (1, 2, 3) returns TRUE; 1 NOT IN (1, 2, NULL) returns FALSE; 4 NOT IN (1, 2, NULL) returns UNKNOWN.

EXISTS (sub-query)

Returns TRUE if sub-query returns at least one row. Only supported if the operation can be rewritten in a join and group operation.

Note: For streaming queries the operation is rewritten in a join and group operation. The required state to compute the query result might grow infinitely depending on the number of distinct input rows. Please provide a query configuration with valid retention interval to prevent excessive state size. See Query Configuration for details.

value IN (sub-query)

Returns TRUE if value is equal to a row returned by sub-query.

Note: For streaming queries the operation is rewritten in a join and group operation. The required state to compute the query result might grow infinitely depending on the number of distinct input rows. Please provide a query configuration with valid retention interval to prevent excessive state size. See Query Configuration for details.

value NOT IN (sub-query)

Returns TRUE if value is not equal to every row returned by sub-query.

Note: For streaming queries the operation is rewritten in a join and group operation. The required state to compute the query result might grow infinitely depending on the number of distinct input rows. Please provide a query configuration with valid retention interval to prevent excessive state size. See Query Configuration for details.

Comparison functions Description
ANY1 === ANY2

Returns TRUE if ANY1 is equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 !== ANY2

Returns TRUE if ANY1 is not equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 > ANY2

Returns TRUE if ANY1 is greater than ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 >= ANY2

Returns TRUE if ANY1 is greater than or equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 < ANY2

Returns TRUE if ANY1 is less than ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 <= ANY2

Returns TRUE if ANY1 is less than or equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY.isNull

Returns TRUE if ANY is NULL.

ANY.isNotNull

Returns TRUE if ANY is not NULL.

STRING1.like(STRING2)

Returns TRUE if STRING1 matches pattern STRING2; returns UNKNOWN if STRING1 or STRING2 is NULL.

E.g., "JoKn".like("Jo_n%") returns TRUE.

STRING.similar(STRING)

Returns TRUE if STRING1 matches SQL regular expression STRING2; returns UNKNOWN if STRING1 or STRING2 is NULL.

E.g., "A".similar("A+") returns TRUE.

ANY1.in(ANY2, ANY3, ...)

Returns TRUE if ANY1 exists in a given list (ANY2, ANY3, ...). When (ANY2, ANY3, ...). contains NULL, returns TRUE if the element can be found and UNKNOWN otherwise. Always returns UNKNOWN if ANY1 is NULL.

E.g., 4.in(1, 2, 3) returns FALSE.

ANY.in(TABLE)

Returns TRUE if ANY is equal to a row returned by sub-query TABLE.

Note: For streaming queries the operation is rewritten in a join and group operation. The required state to compute the query result might grow infinitely depending on the number of distinct input rows. Please provide a query configuration with valid retention interval to prevent excessive state size. See Query Configuration for details.

ANY1.between(ANY2, ANY3)

Returns TRUE if ANY1 is greater than or equal to ANY2 and less than or equal to ANY3. When either ANY2 or ANY3 is NULL, returns FALSE or UNKNOWN.

E.g., 12.between(15, 12) returns FALSE; 12.between(10, Null(INT)) returns UNKNOWN; 12.between(Null(INT), 10) returns FALSE.

ANY1.notBetween(ANY2, ANY3)

Returns TRUE if ANY1 is less than ANY2 or greater than ANY3. When either ANY2 or ANY3 is NULL, returns TRUE or UNKNOWN.

E.g., 12.notBetween(15, 12) returns TRUE; 12.notBetween(Null(INT), 15) returns UNKNOWN; 12.notBetween(15, Null(INT)) returns TRUE.

Comparison functions Description
ANY1 === ANY2

Returns TRUE if ANY1 is equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 !== ANY2

Returns TRUE if ANY1 is not equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 > ANY2

Returns TRUE if ANY1 is greater than ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 >= ANY2

Returns TRUE if ANY1 is greater than or equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 < ANY2

Returns TRUE if ANY1 is less than ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY1 <= ANY2

Returns TRUE if ANY1 is less than or equal to ANY2; returns UNKNOWN if ANY1 or ANY2 is NULL.

ANY.isNull

Returns TRUE if ANY is NULL.

ANY.isNotNull

Returns TRUE if ANY is not NULL.

STRING1.like(STRING2)

Returns TRUE if STRING1 matches pattern STRING2; returns UNKNOWN if STRING1 or STRING2 is NULL.

E.g., "JoKn".like("Jo_n%") returns TRUE.

STRING1.similar(STRING2)

Returns TRUE if STRING1 matches SQL regular expression STRING2; returns UNKNOWN if STRING1 or STRING2 is NULL.

E.g., "A".similar("A+") returns TRUE.

ANY1.in(ANY2, ANY3, ...)

Returns TRUE if ANY1 exists in a given list (ANY2, ANY3, ...). When (ANY2, ANY3, ...). contains NULL, returns TRUE if the element can be found and UNKNOWN otherwise. Always returns UNKNOWN if ANY1 is NULL.

E.g., 4.in(1, 2, 3) returns FALSE.

ANY.in(TABLE)

Returns TRUE if ANY is equal to a row returned by sub-query TABLE.

Note: For streaming queries the operation is rewritten in a join and group operation. The required state to compute the query result might grow infinitely depending on the number of distinct input rows. Please provide a query configuration with valid retention interval to prevent excessive state size. See Query Configuration for details.

ANY1.between(ANY2, ANY3)

Returns TRUE if ANY1 is greater than or equal to ANY2 and less than or equal to ANY3. When either ANY2 or ANY3 is NULL, returns FALSE or UNKNOWN.

E.g., 12.between(15, 12) returns FALSE; 12.between(10, Null(Types.INT)) returns UNKNOWN; 12.between(Null(Types.INT), 10) returns FALSE.

ANY1.notBetween(ANY2, ANY3)

Returns TRUE if ANY1 is less than ANY2 or greater than ANY3. When either ANY2 or ANY3 is NULL, returns TRUE or UNKNOWN.

E.g., 12.notBetween(15, 12) returns TRUE; 12.notBetween(Null(Types.INT), 15) returns UNKNOWN; 12.notBetween(15, Null(Types.INT)) returns TRUE.

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Logical Functions

Logical functions Description
boolean1 OR boolean2

Returns TRUE if boolean1 is TRUE or boolean2 is TRUE. Supports three-valued logic.

E.g., TRUE OR UNKNOWN returns TRUE.

boolean1 AND boolean2

Returns TRUE if boolean1 and boolean2 are both TRUE. Supports three-valued logic.

E.g., TRUE AND UNKNOWN returns UNKNOWN.

NOT boolean

Returns TRUE if boolean is FALSE; returns FALSE if boolean is TRUE; returns UNKNOWN if boolean is UNKNOWN.

boolean IS FALSE

Returns TRUE if boolean is FALSE; returns FALSE if boolean is TRUE or UNKNOWN.

boolean IS NOT FALSE

Returns TRUE if boolean is TRUE or UNKNOWN; returns FALSE if boolean is FALSE.

boolean IS TRUE

Returns TRUE if boolean is TRUE; returns FALSE if boolean is FALSE or UNKNOWN.

boolean IS NOT TRUE

Returns TRUE if boolean is FALSE or UNKNOWN; returns FALSE if boolean is FALSE.

boolean IS UNKNOWN

Returns TRUE if boolean is UNKNOWN; returns FALSE if boolean is TRUE or FALSE.

boolean IS NOT UNKNOWN

Returns TRUE if boolean is TRUE or FALSE; returns FALSE if boolean is UNKNOWN.

Logical functions Description
BOOLEAN1 || BOOLEAN2

Returns TRUE if BOOLEAN1 is TRUE or BOOLEAN2 is TRUE. Supports three-valued logic.

E.g., true || Null(BOOLEAN) returns TRUE.

BOOLEAN1 && BOOLEAN2

Returns TRUE if BOOLEAN1 and BOOLEAN2 are both TRUE. Supports three-valued logic.

E.g., true && Null(BOOLEAN) returns UNKNOWN.

!BOOLEAN

Returns TRUE if BOOLEAN is FALSE; returns FALSE if BOOLEAN is TRUE; returns UNKNOWN if BOOLEAN is UNKNOWN.

BOOLEAN.isTrue

Returns TRUE if BOOLEAN is TRUE; returns FALSE if BOOLEAN is FALSE or UNKNOWN.

BOOLEAN.isFalse

Returns TRUE if BOOLEAN is FALSE; returns FALSE if BOOLEAN is TRUE or UNKNOWN.

BOOLEAN.isNotTrue

Returns TRUE if BOOLEAN is FALSE or UNKNOWN; returns FALSE if BOOLEAN is FALSE.

BOOLEAN.isNotFalse

Returns TRUE if BOOLEAN is TRUE or UNKNOWN; returns FALSE if BOOLEAN is FALSE.

Logical functions Description
BOOLEAN1 || BOOLEAN2

Returns TRUE if BOOLEAN1 is TRUE or BOOLEAN2 is TRUE. Supports three-valued logic.

E.g., true || Null(Types.BOOLEAN) returns TRUE.

BOOLEAN1 && BOOLEAN2

Returns TRUE if BOOLEAN1 and BOOLEAN2 are both TRUE. Supports three-valued logic.

E.g., true && Null(Types.BOOLEAN) returns UNKNOWN.

!BOOLEAN

Returns TRUE if BOOLEAN is FALSE; returns FALSE if BOOLEAN is TRUE; returns UNKNOWN if BOOLEAN is UNKNOWN.

BOOLEAN.isTrue

Returns TRUE if BOOLEAN is TRUE; returns FALSE if BOOLEAN is FALSE or UNKNOWN.

BOOLEAN.isFalse

Returns TRUE if BOOLEAN is FALSE; returns FALSE if BOOLEAN is TRUE or UNKNOWN.

BOOLEAN.isNotTrue

Returns TRUE if BOOLEAN is FALSE or UNKNOWN; returns FALSE if BOOLEAN is FALSE.

BOOLEAN.isNotFalse

Returns TRUE if BOOLEAN is TRUE or UNKNOWN; returns FALSE if BOOLEAN is FALSE.

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Arithmetic Functions

Arithmetic functions Description
+ numeric

Returns numeric.

- numeric

Returns negative numeric.

numeric1 + numeric2

Returns numeric1 plus numeric2.

numeric1 - numeric2

Returns numeric1 minus numeric2.

numeric1 * numeric2

Returns numeric1 multiplied by numeric2.

numeric1 / numeric2

Returns numeric1 divided by numeric2.

POWER(numeric1, numeric2)

Returns numeric1 raised to the power of numeric2.

ABS(numeric)

Returns the absolute value of numeric.

MOD(numeric1, numeric2)

Returns the remainder (modulus) of numeric1 divided by numeric2. The result is negative only if numeric1 is negative.

SQRT(numeric)

Returns the square root of numeric.

LN(numeric)

Returns the natural logarithm (base e) of numeric.

LOG10(numeric)

Returns the base 10 logarithm of numeric.

LOG2(numeric)

Returns the base 2 logarithm of numeric.

LOG(numeric2)
LOG(numeric1, numeric2)

When called with one argument, returns the natural logarithm of numeric2. When called with two arguments, this function returns the logarithm of numeric2 to the base numeric1.

Note: Currently, numeric2 must be greater than 0 and numeric1 must be greater than 1.

EXP(numeric)

Returns e raised to the power of numeric.

CEIL(numeric)
CEILING(numeric)

Rounds numeric up, and returns the smallest number that is greater than or equal to numeric.

FLOOR(numeric)

Rounds numeric down, and returns the largest number that is less than or equal to numeric.

SIN(numeric)

Returns the sine of numeric.

SINH(numeric)

Returns the hyperbolic sine of numeric.

The return type is DOUBLE.

COS(numeric)

Returns the cosine of numeric.

TAN(numeric)

Returns the tangent of numeric.

TANH(numeric)

Returns the hyperbolic tangent of numeric.

The return type is DOUBLE.

COT(numeric)

Returns the cotangent of a numeric.

ASIN(numeric)

Returns the arc sine of numeric.

ACOS(numeric)

Returns the arc cosine of numeric.

ATAN(numeric)

Returns the arc tangent of numeric.

ATAN2(numeric1, numeric2)

Returns the arc tangent of a coordinate (numeric1, numeric2).

COSH(numeric)

Returns the hyperbolic cosine of NUMERIC.

Return value type is DOUBLE.

DEGREES(numeric)

Returns the degree representation of a radian numeric.

RADIANS(numeric)

Returns the radian representation of a degree numeric.

SIGN(numeric)

Returns the signum of numeric.

ROUND(numeric, integer)

Returns a number rounded to integer decimal places for numeric.

PI

Returns a value that is closer than any other values to pi.

E()

Returns a value that is closer than any other values to e.

RAND()

Returns a pseudorandom double value between 0.0 (inclusive) and 1.0 (exclusive).

RAND(integer)

Returns a pseudorandom double value between 0.0 (inclusive) and 1.0 (exclusive) with an initial seed integer. Two RAND functions will return identical sequences of numbers if they have the same initial seed.

RAND_INTEGER(integer)

Returns a pseudorandom integer value between 0 (inclusive) and integer (exclusive).

RAND_INTEGER(integer1, integer2)

Returns a pseudorandom integer value between 0 (inclusive) and the specified value (exclusive) with an initial seed. Two RAND_INTEGER functions will return identical sequences of numbers if they have the same initial seed and bound.

UUID()

Returns an UUID (Universally Unique Identifier) string (e.g., "3d3c68f7-f608-473f-b60c-b0c44ad4cc4e") according to RFC 4122 type 4 (pseudo randomly generated) UUID. The UUID is generated using a cryptographically strong pseudo random number generator.

BIN(integer)

Returns a string representation of integer in binary format. Returns NULL if integer is NULL.

E.g. BIN(4) returns '100' and BIN(12) returns '1100'.

HEX(numeric)
HEX(string)
      

Returns a string representation of an integer numeric value or a string in hex format. Returns NULL if the argument is NULL.

E.g. a numeric 20 leads to "14", a numeric 100 leads to "64", a string "hello,world" leads to "68656C6C6F2C776F726C64".

Arithmetic functions Description
+ NUMERIC

Returns NUMERIC.

- NUMERIC

Returns negative NUMERIC.

NUMERIC1 + NUMERIC2

Returns NUMERIC1 plus NUMERIC2.

NUMERIC1 - NUMERIC2

Returns NUMERIC1 minus NUMERIC2.

NUMERIC1 * NUMERIC2

Returns NUMERIC1 multiplied by NUMERIC2.

NUMERIC1 / NUMERIC2

Returns NUMERIC1 divided by NUMERIC2.

NUMERIC1.power(NUMERIC2)

Returns NUMERIC1 raised to the power of NUMERIC2.

NUMERIC.abs()

Returns the absolute value of NUMERIC.

NUMERIC1 % NUMERIC2

Returns the remainder (modulus) of NUMERIC1 divided by NUMERIC2. The result is negative only if numeric1 is negative.

NUMERIC.sqrt()

Returns the square root of NUMERIC.

NUMERIC.ln()

Returns the natural logarithm (base e) of NUMERIC.

NUMERIC.log10()

Returns the base 10 logarithm of NUMERIC.

NUMERIC.log2()

Returns the base 2 logarithm of NUMERIC.

NUMERIC1.log()
NUMERIC1.log(NUMERIC2)

When called without argument, returns the natural logarithm of NUMERIC1. When called with an argument, returns the logarithm of NUMERIC1 to the base NUMERIC2.

Note: Currently, NUMERIC1 must be greater than 0 and NUMERIC2 must be greater than 1.

NUMERIC.exp()

Returns e raised to the power of NUMERIC.

NUMERIC.ceil()

Rounds NUMERIC up, and returns the smallest number that is greater than or equal to NUMERIC.

NUMERIC.floor()

Rounds NUMERIC down, and returns the largest number that is less than or equal to NUMERIC.

NUMERIC.sin()

Returns the sine of NUMERIC.

NUMERIC.sinh()

Returns the hyperbolic sine of NUMERIC.

The return type is DOUBLE.

NUMERIC.cos()

Returns the cosine of NUMERIC.

NUMERIC.tan()

Returns the tangent of NUMERIC.

NUMERIC.tanh()

Returns the hyperbolic tangent of NUMERIC.

The return type is DOUBLE.

NUMERIC.cot()

Returns the cotangent of a NUMERIC.

NUMERIC.asin()

Returns the arc sine of NUMERIC.

NUMERIC.acos()

Returns the arc cosine of NUMERIC.

NUMERIC.atan()

Returns the arc tangent of NUMERIC.

atan2(NUMERIC1, NUMERIC2)

Returns the arc tangent of a coordinate (NUMERIC1, NUMERIC2).

NUMERIC.cosh()

Returns the hyperbolic cosine of NUMERIC.

Return value type is DOUBLE.

NUMERIC.degrees()

Returns the degree representation of a radian NUMERIC.

NUMERIC.radians()

Returns the radian representation of a degree NUMERIC.

NUMERIC.sign()

Returns the signum of NUMERIC.

NUMERIC.round(INT)

Returns a number rounded to INT decimal places for NUMERIC.

pi()

Returns a value that is closer than any other values to pi.

e()

Returns a value that is closer than any other values to e.

rand()

Returns a pseudorandom double value between 0.0 (inclusive) and 1.0 (exclusive).

rand(INTEGER)

Returns a pseudorandom double value between 0.0 (inclusive) and 1.0 (exclusive) with an initial seed INTEGER. Two RAND functions will return identical sequences of numbers if they have the same initial seed.

randInteger(INTEGER)

Returns a pseudorandom integer value between 0 (inclusive) and INTEGER (exclusive).

randInteger(INTEGER1, INTEGER2)

Returns a pseudorandom integer value between 0 (inclusive) and INTEGER2 (exclusive) with an initial seed INTEGER1. Two randInteger functions will return identical sequences of numbers if they have same initial seed and bound.

uuid()

Returns an UUID (Universally Unique Identifier) string (e.g., "3d3c68f7-f608-473f-b60c-b0c44ad4cc4e") according to RFC 4122 type 4 (pseudo randomly generated) UUID. The UUID is generated using a cryptographically strong pseudo random number generator.

INTEGER.bin()

Returns a string representation of INTEGER in binary format. Returns NULL if INTEGER is NULL.

E.g., 4.bin() returns "100" and 12.bin() returns "1100".

NUMERIC.hex()
STRING.hex()

Returns a string representation of an integer NUMERIC value or a STRING in hex format. Returns NULL if the argument is NULL.

E.g. a numeric 20 leads to "14", a numeric 100 leads to "64", a string "hello,world" leads to "68656C6C6F2C776F726C64".

Arithmetic functions Description
+ NUMERIC

Returns NUMERIC.

- NUMERIC

Returns negative NUMERIC.

NUMERIC1 + NUMERIC2

Returns NUMERIC1 plus NUMERIC2.

NUMERIC1 - NUMERIC2

Returns NUMERIC1 minus NUMERIC2.

NUMERIC1 * NUMERIC2

Returns NUMERIC1 multiplied by NUMERIC2.

NUMERIC1 / NUMERIC2

Returns NUMERIC1 divided by NUMERIC2.

NUMERIC1.power(NUMERIC2)

Returns NUMERIC1 raised to the power of NUMERIC2.

NUMERIC.abs()

Returns the absolute value of NUMERIC.

NUMERIC1 % NUMERIC2

Returns the remainder (modulus) of NUMERIC1 divided by NUMERIC2. The result is negative only if numeric1 is negative.

NUMERIC.sqrt()

Returns the square root of NUMERIC.

NUMERIC.ln()

Returns the natural logarithm (base e) of NUMERIC.

NUMERIC.log10()

Returns the base 10 logarithm of NUMERIC.

NUMERIC.log2()

Returns the base 2 logarithm of NUMERIC.

NUMERIC1.log()
NUMERIC1.log(NUMERIC2)

When called without argument, returns the natural logarithm of NUMERIC1. When called with an argument, returns the logarithm of NUMERIC1 to the base NUMERIC2.

Note: Currently, NUMERIC1 must be greater than 0 and NUMERIC2 must be greater than 1.

NUMERIC.exp()

Returns e raised to the power of NUMERIC.

NUMERIC.ceil()

Rounds NUMERIC up, and returns the smallest number that is greater than or equal to NUMERIC.

NUMERIC.floor()

Rounds NUMERIC down, and returns the largest number that is less than or equal to NUMERIC.

NUMERIC.sin()

Returns the sine of NUMERIC.

NUMERIC.sinh()

Returns the hyperbolic sine of NUMERIC.

The return type is DOUBLE.

NUMERIC.cos()

Returns the cosine of NUMERIC.

NUMERIC.tan()

Returns the tangent of NUMERIC.

NUMERIC.tanh()

Returns the hyperbolic tangent of NUMERIC.

The return type is DOUBLE.

NUMERIC.cot()

Returns the cotangent of a NUMERIC.

NUMERIC.asin()

Returns the arc sine of NUMERIC.

NUMERIC.acos()

Returns the arc cosine of NUMERIC.

NUMERIC.atan()

Returns the arc tangent of NUMERIC.

atan2(NUMERIC1, NUMERIC2)

Returns the arc tangent of a coordinate (NUMERIC1, NUMERIC2).

NUMERIC.cosh()

Returns the hyperbolic cosine of NUMERIC.

Return value type is DOUBLE.

NUMERIC.degrees()

Returns the degree representation of a radian NUMERIC.

NUMERIC.radians()

Returns the radian representation of a degree NUMERIC.

NUMERIC.sign()

Returns the signum of NUMERIC.

NUMERIC.round(INT)

Returns a number rounded to INT decimal places for NUMERIC.

pi()

Returns a value that is closer than any other values to pi.

e()

Returns a value that is closer than any other values to e.

rand()

Returns a pseudorandom double value between 0.0 (inclusive) and 1.0 (exclusive).

rand(INTEGER)

Returns a pseudorandom double value between 0.0 (inclusive) and 1.0 (exclusive) with an initial seed INTEGER. Two RAND functions will return identical sequences of numbers if they have the same initial seed.

randInteger(INTEGER)

Returns a pseudorandom integer value between 0 (inclusive) and INTEGER (exclusive).

randInteger(INTEGER1, INTEGER2)

Returns a pseudorandom integer value between 0 (inclusive) and INTEGER2 (exclusive) with an initial seed INTEGER1. Two randInteger functions will return identical sequences of numbers if they have same initial seed and bound.

uuid()

Returns an UUID (Universally Unique Identifier) string (e.g., "3d3c68f7-f608-473f-b60c-b0c44ad4cc4e") according to RFC 4122 type 4 (pseudo randomly generated) UUID. The UUID is generated using a cryptographically strong pseudo random number generator.

INTEGER.bin()

Returns a string representation of INTEGER in binary format. Returns NULL if INTEGER is NULL.

E.g., 4.bin() returns "100" and 12.bin() returns "1100".

NUMERIC.hex()
STRING.hex()

Returns a string representation of an integer NUMERIC value or a STRING in hex format. Returns NULL if the argument is NULL.

E.g. a numeric 20 leads to "14", a numeric 100 leads to "64", a string "hello,world" leads to "68656C6C6F2C776F726C64".

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String Functions

String functions Description
string1 || string2

Returns the concatenation of string1 and string2.

CHAR_LENGTH(string)
CHARACTER_LENGTH(string)

Returns the number of characters in string.

UPPER(string)

Returns string in uppercase.

LOWER(string)

Returns string in lowercase.

POSITION(string1 IN string2)

Returns the position (start from 1) of the first occurrence of string1 in string2; returns 0 if string1 cannot be found in string2.

TRIM([ BOTH | LEADING | TRAILING ] string1 FROM string2)

Returns a string that removes leading and/or trailing characters string1 from string2. By default, whitespaces at both sides are removed.

LTRIM(string)

Returns a string that removes the left whitespaces from string.

E.g., LTRIM(' This is a test String.') returns "This is a test String.".

RTRIM(string)

Returns a string that removes the right whitespaces from string.

E.g., RTRIM('This is a test String. ') returns "This is a test String.".

REPEAT(string, integer)

Returns a string that repeats the base string integer times.

E.g., REPEAT('This is a test String.', 2) returns "This is a test String.This is a test String.".

REGEXP_REPLACE(string1, string2, string3)

Returns a string from string1 with all the substrings that match a regular expression string2 consecutively being replaced with string3.

E.g., REGEXP_REPLACE('foobar', 'oo|ar', '') returns "fb".

OVERLAY(string1 PLACING string2 FROM integer1 [ FOR integer2 ])

Returns a string that replaces integer2 (string2's length by default) characters of string1 with string2 from position integer1.

E.g., OVERLAY('This is an old string' PLACING ' new' FROM 10 FOR 5) returns "This is a new string"

SUBSTRING(string FROM integer1 [ FOR integer2 ])

Returns a substring of string starting from position integer1 with length integer2 (to the end by default).

REPLACE(string1, string2, string3)

Returns a new string which replaces all the occurrences of string2 with string3 (non-overlapping) from string1

E.g., REPLACE("hello world", "world", "flink") returns "hello flink"; REPLACE("ababab", "abab", "z") returns "zab".

REGEXP_EXTRACT(string1, string2[, integer])

Returns a string from string1 which extracted with a specified regular expression string2 and a regex match group index integer.

Note: The regex match group index starts from 1 and 0 means matching the whole regex. In addition, the regex match group index should not exceed the number of the defined groups.

E.g. REGEXP_EXTRACT('foothebar', 'foo(.*?)(bar)', 2)" returns "bar".

INITCAP(string)

Returns a new form of string with the first character of each word converted to uppercase and the rest characters to lowercase. Here a word means a sequences of alphanumeric characters.

CONCAT(string1, string2,...)

Returns a string that concatenates string1, string2, .... Returns NULL if any argument is NULL.

E.g., CONCAT('AA', 'BB', 'CC') returns "AABBCC".

CONCAT_WS(string1, string2, string3,...)

Returns a string that concatenates string2, string3, ... with a separator string1. The separator is added between the strings to be concatenated. Returns NULL If string1 is NULL. Compared with CONCAT(), CONCAT_WS() automatically skips NULL arguments.

E.g., CONCAT_WS('~', 'AA', NULL, 'BB', '', 'CC') returns "AA~BB~~CC".

LPAD(string1, integer, string2)

Returns a new string from string1 left-padded with string2 to a length of integer characters. If the length of string1 is shorter than integer, returns string1 shortened to integer characters.

E.g., LPAD('hi',4,'??') returns "??hi"; LPAD('hi',1,'??') returns "h".

RPAD(string1, integer, string2)

Returns a new string from string1 right-padded with string2 to a length of integer characters. If the length of string1 is shorter than integer, returns string1 shortened to integer characters.

E.g., RPAD('hi',4,'??') returns "hi??", RPAD('hi',1,'??') returns "h".

FROM_BASE64(string)

Returns the base64-decoded result from string; returns NULL if string is NULL.

E.g., FROM_BASE64('aGVsbG8gd29ybGQ=') returns "hello world".

TO_BASE64(string)

Returns the base64-encoded result from string; returns NULL if string is NULL.

E.g., TO_BASE64('hello world') returns "aGVsbG8gd29ybGQ=".

String functions Description
STRING1 + STRING2

Returns the concatenation of STRING1 and STRING2.

STRING.charLength()

Returns the number of characters in STRING.

STRING.upperCase()

Returns STRING in uppercase.

STRING.lowerCase()

Returns STRING in lowercase.

STRING1.position(STRING2)

Returns the position (start from 1) of the first occurrence of STRING1 in STRING2; returns 0 if STRING1 cannot be found in STRING2.

STRING1.trim(LEADING, STRING2)
STRING1.trim(TRAILING, STRING2)
STRING1.trim(BOTH, STRING2)
STRING1.trim(BOTH)
STRING1.trim()

Returns a string that removes leading and/or trailing characters STRING2 from STRING1. By default, whitespaces at both sides are removed.

STRING.ltrim()

Returns a string that removes the left whitespaces from STRING.

E.g., ' This is a test String.'.ltrim() returns "This is a test String.".

STRING.rtrim()

Returns a string that removes the right whitespaces from STRING.

E.g., 'This is a test String. '.rtrim() returns "This is a test String.".

STRING.repeat(INT)

Returns a string that repeats the base STRING INT times.

E.g., 'This is a test String.'.repeat(2) returns "This is a test String.This is a test String.".

STRING1.regexpReplace(STRING2, STRING3)

Returns a string from STRING1 with all the substrings that match a regular expression STRING2 consecutively being replaced with STRING3.

E.g., 'foobar'.regexpReplace('oo|ar', '') returns "fb".

STRING1.overlay(STRING2, INT1)
STRING1.overlay(STRING2, INT1, INT2)

Returns a string that replaces INT2 (STRING2's length by default) characters of STRING1 with STRING2 from position INT1.

E.g., 'xxxxxtest'.overlay('xxxx', 6) returns "xxxxxxxxx"; 'xxxxxtest'.overlay('xxxx', 6, 2) returns "xxxxxxxxxst".

STRING.substring(INT1)
STRING.substring(INT1, INT2)

Returns a substring of STRING starting from position INT1 with length INT2 (to the end by default).

STRING1.replace(STRING2, STRING3)

Returns a new string which replaces all the occurrences of STRING2 with STRING3 (non-overlapping) from STRING1.

E.g., 'hello world'.replace('world', 'flink') returns 'hello flink'; 'ababab'.replace('abab', 'z') returns 'zab'.

STRING1.regexpExtract(STRING2[, INTEGER1])

Returns a string from STRING1 which extracted with a specified regular expression STRING2 and a regex match group index INTEGER1.

Note: The regex match group index starts from 1 and 0 means matching the whole regex. In addition, the regex match group index should not exceed the number of the defined groups.

E.g. 'foothebar'.regexpExtract('foo(.*?)(bar)', 2)" returns "bar".

STRING.initCap()

Returns a new form of STRING with the first character of each word converted to uppercase and the rest characters to lowercase. Here a word means a sequences of alphanumeric characters.

concat(STRING1, STRING2, ...)

Returns a string that concatenates STRING1, STRING2, .... Returns NULL if any argument is NULL.

E.g., concat('AA', 'BB', 'CC') returns "AABBCC".

concat_ws(STRING1, STRING2, STRING3, ...)

Returns a string that concatenates STRING2, STRING3, ... with a separator STRING1. The separator is added between the strings to be concatenated. Returns NULL If STRING1 is NULL. Compared with concat(), concat_ws() automatically skips NULL arguments.

E.g., concat_ws('~', 'AA', Null(STRING), 'BB', '', 'CC') returns "AA~BB~~CC".

STRING1.lpad(INT, STRING2)

Returns a new string from STRING1 left-padded with STRING2 to a length of INT characters. If the length of STRING1 is shorter than INT, returns STRING1 shortened to INT characters.

E.g., 'hi'.lpad(4, '??') returns "??hi"; 'hi'.lpad(1, '??') returns "h".

STRING1.rpad(INT, STRING2)

Returns a new string from STRING1 right-padded with STRING2 to a length of INT characters. If the length of STRING1 is shorter than INT, returns STRING1 shortened to INT characters.

E.g., 'hi'.rpad(4, '??') returns "hi??"; 'hi'.rpad(1, '??') returns "h".

STRING.fromBase64()

Returns the base64-decoded result from STRING; returns NULL if STRING is NULL.

E.g., 'aGVsbG8gd29ybGQ='.fromBase64() returns "hello world".

STRING.toBase64()

Returns the base64-encoded result from STRING; returns NULL if STRING is NULL.

E.g., 'hello world'.toBase64() returns "aGVsbG8gd29ybGQ=".

String functions Description
STRING1 + STRING2

Returns the concatenation of STRING1 and STRING2.

STRING.charLength()

Returns the number of characters in STRING.

STRING.upperCase()

Returns STRING in uppercase.

STRING.lowerCase()

Returns STRING in lowercase.

STRING1.position(STRING2)

Returns the position (start from 1) of the first occurrence of STRING1 in STRING2; returns 0 if STRING1 cannot be found in STRING2.

STRING.trim(
  leading = true,
  trailing = true,
  character = " ")

Returns a string that removes leading and/or trailing characters from STRING.

STRING.ltrim()

Returns a string that removes the left whitespaces from STRING.

E.g., " This is a test String.".ltrim() returns "This is a test String.".

STRING.rtrim()

Returns a string that removes the right whitespaces from STRING.

E.g., "This is a test String. ".rtrim() returns "This is a test String.".

STRING.repeat(INT)

Returns a string that repeats the base STRING INT times.

E.g., "This is a test String.".repeat(2) returns "This is a test String.This is a test String.".

STRING1.regexpReplace(STRING2, STRING3)

Returns a string from STRING1 with all the substrings that match a regular expression STRING2 consecutively being replaced with STRING3.

E.g. "foobar".regexpReplace("oo|ar", "") returns "fb".

STRING1.overlay(STRING2, INT1)
STRING1.overlay(STRING2, INT1, INT2)

Returns a string that replaces INT2 (STRING2's length by default) characters of STRING1 with STRING2 from position INT1.

E.g., "xxxxxtest".overlay("xxxx", 6) returns "xxxxxxxxx"; "xxxxxtest".overlay("xxxx", 6, 2) returns "xxxxxxxxxst".

STRING.substring(INT1)
STRING.substring(INT1, INT2)

Returns a substring of STRING starting from position INT1 with length INT2 (to the end by default).

STRING1.replace(STRING2, STRING3)

Returns a new string which replaces all the occurrences of STRING2 with STRING3 (non-overlapping) from STRING1.

E.g., "hello world".replace("world", "flink") returns "hello flink"; "ababab".replace("abab", "z") returns "zab".

STRING1.regexpExtract(STRING2[, INTEGER1])

Returns a string from STRING1 which extracted with a specified regular expression STRING2 and a regex match group index INTEGER1.

Note: The regex match group index starts from 1 and 0 means matching the whole regex. In addition, the regex match group index should not exceed the number of the defined groups.

E.g. "foothebar".regexpExtract("foo(.*?)(bar)", 2)" returns "bar".

STRING.initCap()

Returns a new form of STRING with the first character of each word converted to uppercase and the rest characters to lowercase. Here a word means a sequences of alphanumeric characters.

concat(STRING1, STRING2, ...)

Returns a string that concatenates STRING1, STRING2, .... Returns NULL if any argument is NULL.

E.g., concat("AA", "BB", "CC") returns "AABBCC".

concat_ws(STRING1, STRING2, STRING3, ...)

Returns a string that concatenates STRING2, STRING3, ... with a separator STRING1. The separator is added between the strings to be concatenated. Returns NULL If STRING1 is NULL. Compared with concat(), concat_ws() automatically skips NULL arguments.

E.g., concat_ws("~", "AA", Null(Types.STRING), "BB", "", "CC") returns "AA~BB~~CC".

STRING1.lpad(INT, STRING2)

Returns a new string from STRING1 left-padded with STRING2 to a length of INT characters. If the length of STRING1 is shorter than INT, returns STRING1 shortened to INT characters.

E.g., "hi".lpad(4, "??") returns "??hi"; "hi".lpad(1, "??") returns "h".

STRING1.rpad(INT, STRING2)

Returns a new string from STRING1 right-padded with STRING2 to a length of INT characters. If the length of STRING1 is shorter than INT, returns STRING1 shortened to INT characters.

E.g., "hi".rpad(4, "??") returns "hi??"; "hi".rpad(1, "??") returns "h".

STRING.fromBase64()

Returns the base64-decoded result from STRING; returns null If STRING is NULL.

E.g., "aGVsbG8gd29ybGQ=".fromBase64() returns "hello world".

STRING.toBase64()

Returns the base64-encoded result from STRING; returns NULL if STRING is NULL.

E.g., "hello world".toBase64() returns "aGVsbG8gd29ybGQ=".

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Temporal Functions

Temporal functions Description
DATE string

Returns a SQL date parsed from string in form of "yyyy-MM-dd".

TIME string

Returns a SQL time parsed from string in form of "HH:mm:ss".

TIMESTAMP string

Returns a SQL timestamp parsed from string in form of "yyyy-MM-dd HH:mm:ss[.SSS]".

INTERVAL string range

Parses an interval string in the form "dd hh:mm:ss.fff" for SQL intervals of milliseconds or "yyyy-mm" for SQL intervals of months. An interval range might be DAY, MINUTE, DAY TO HOUR, or DAY TO SECOND for intervals of milliseconds; YEAR or YEAR TO MONTH for intervals of months.

E.g., INTERVAL '10 00:00:00.004' DAY TO SECOND, INTERVAL '10' DAY, or INTERVAL '2-10' YEAR TO MONTH return intervals.

CURRENT_DATE

Returns the current SQL date in the UTC time zone.

CURRENT_TIME

Returns the current SQL time in the UTC time zone.

CURRENT_TIMESTAMP

Returns the current SQL timestamp in the UTC time zone.

LOCALTIME

Returns the current SQL time in local time zone.

LOCALTIMESTAMP

Returns the current SQL timestamp in local time zone.

EXTRACT(timeintervalunit FROM temporal)

Returns a long value extracted from the timeintervalunit part of temporal.

E.g., EXTRACT(DAY FROM DATE '2006-06-05') returns 5.

YEAR(date)

Returns the year from SQL date date. Equivalent to EXTRACT(YEAR FROM date).

E.g., YEAR(DATE '1994-09-27') returns 1994.

QUARTER(date)

Returns the quarter of a year (an integer between 1 and 4) from SQL date date. Equivalent to EXTRACT(QUARTER FROM date).

E.g., QUARTER(DATE '1994-09-27') returns 3.

MONTH(date)

Returns the month of a year (an integer between 1 and 12) from SQL date date. Equivalent to EXTRACT(MONTH FROM date).

E.g., MONTH(DATE '1994-09-27') returns 9.

WEEK(date)

Returns the week of a year (an integer between 1 and 53) from SQL date date. Equivalent to EXTRACT(WEEK FROM date).

E.g., WEEK(DATE '1994-09-27') returns 39.

DAYOFYEAR(date)

Returns the day of a year (an integer between 1 and 366) from SQL date date. Equivalent to EXTRACT(DOY FROM date).

E.g., DAYOFYEAR(DATE '1994-09-27') returns 270.

DAYOFMONTH(date)

Returns the day of a month (an integer between 1 and 31) from SQL date date. Equivalent to EXTRACT(DAY FROM date).

E.g., DAYOFMONTH(DATE '1994-09-27') returns 27.

DAYOFWEEK(date)

Returns the day of a week (an integer between 1 and 7; Sunday = 1) from SQL date date.Equivalent to EXTRACT(DOW FROM date).

E.g., DAYOFWEEK(DATE '1994-09-27') returns 3.

HOUR(timestamp)

Returns the hour of a day (an integer between 0 and 23) from SQL timestamp timestamp. Equivalent to EXTRACT(HOUR FROM timestamp).

E.g., HOUR(TIMESTAMP '1994-09-27 13:14:15') returns 13.

MINUTE(timestamp)

Returns the minute of an hour (an integer between 0 and 59) from SQL timestamp timestamp. Equivalent to EXTRACT(MINUTE FROM timestamp).

E.g., MINUTE(TIMESTAMP '1994-09-27 13:14:15') returns 14.

SECOND(timestamp)

Returns the second of a minute (an integer between 0 and 59) from SQL timestamp. Equivalent to EXTRACT(SECOND FROM timestamp).

E.g., SECOND(TIMESTAMP '1994-09-27 13:14:15') returns 15.

FLOOR(timepoint TO timeintervalunit)

Returns a value that rounds timepoint down to the time unit timeintervalunit.

E.g., FLOOR(TIME '12:44:31' TO MINUTE) returns 12:44:00.

CEIL(timepoint TO timeintervalunit)

Returns a value that rounds timepoint up to the time unit timeintervalunit.

E.g., CEIL(TIME '12:44:31' TO MINUTE) returns 12:45:00.

(timepoint1, temporal1) OVERLAPS (timepoint2, temporal2)

Returns TRUE if two time intervals defined by (timepoint1, temporal1) and (timepoint2, temporal2) overlap. The temporal values could be either a time point or a time interval.

E.g., (TIME '2:55:00', INTERVAL '1' HOUR) OVERLAPS (TIME '3:30:00', INTERVAL '2' HOUR) returns TRUE; (TIME '9:00:00', TIME '10:00:00') OVERLAPS (TIME '10:15:00', INTERVAL '3' HOUR) returns FALSE.

DATE_FORMAT(timestamp, string)

Returns a string that formats timestamp with a specified format string. The format specification is given in the Date Format Specifier table.

TIMESTAMPADD(timeintervalunit, interval, timepoint)

Returns a new time value that adds a (signed) integer interval to timepoint. The unit for interval is given by the unit argument, which should be one of the following values: SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR.

E.g., TIMESTAMPADD(WEEK, 1, DATE '2003-01-02') returns 2003-01-09.

TIMESTAMPDIFF(timepointunit, timepoint1, timepoint2)

Returns the (signed) number of timepointunit between timepoint1 and timepoint2. The unit for the interval is given by the first argument, which should be one of the following values: SECOND, MINUTE, HOUR, DAY, MONTH, or YEAR. See also the Time Interval and Point Unit Specifiers table.

E.g., TIMESTAMPDIFF(DAY, TIMESTAMP '2003-01-02 10:00:00', TIMESTAMP '2003-01-03 10:00:00') leads to 1.

Temporal functions Description
STRING.toDate()

Returns a SQL date parsed from STRING in form of "yyyy-MM-dd".

STRING.toTime()

Returns a SQL time parsed from STRING in form of "HH:mm:ss".

STRING.toTimestamp()

Returns a SQL timestamp parsed from STRING in form of "yyyy-MM-dd HH:mm:ss[.SSS]".

NUMERIC.year
NUMERIC.years

Creates an interval of months for NUMERIC years.

NUMERIC.month
NUMERIC.months

Creates an interval of NUMERIC months.

NUMERIC.day
NUMERIC.days

Creates an interval of milliseconds for NUMERIC days.

NUMERIC.hour
NUMERIC.hours

Creates an interval of milliseconds for NUMERIC hours.

NUMERIC.minute
NUMERIC.minutes

Creates an interval of milliseconds for NUMERIC minutes.

NUMERIC.second
NUMERIC.seconds

Creates an interval of milliseconds for NUMERIC seconds.

NUMERIC.milli
NUMERIC.millis

Creates an interval of NUMERIC milliseconds.

currentDate()

Returns the current SQL date in the UTC time zone.

currentTime()

Returns the current SQL time in the UTC time zone.

currentTimestamp()

Returns the current SQL timestamp in the UTC time zone.

localTime()

Returns the current SQL time in local time zone.

localTimestamp()

Returns the current SQL timestamp in local time zone.

TEMPORAL.extract(TIMEINTERVALUNIT)

Returns a long value extracted from the TIMEINTERVALUNIT part of temporal.

E.g., '2006-06-05'.toDate.extract(DAY) returns 5; '2006-06-05'.toDate.extract(QUARTER) returns 2.

TIMEPOINT.floor(TIMEINTERVALUNIT)

Returns a value that rounds TIMEPOINT down to the time unit TIMEINTERVALUNIT.

E.g., '12:44:31'.toDate.floor(MINUTE) returns 12:44:00.

TIMEPOINT.ceil(TIMEINTERVALUNIT)

Returns a value that rounds TIMEPOINT up to the time unit TIMEINTERVALUNIT.

E.g., '12:44:31'.toTime.floor(MINUTE) returns 12:45:00.

temporalOverlaps(TIMEPOINT1, TEMPORAL1, TIMEPOINT2, TEMPORAL2)

Returns TRUE if two time intervals defined by (TIMEPOINT1, TEMPORAL1) and (TIMEPOINT2, TEMPORAL2) overlap. The temporal values could be either a time point or a time interval.

E.g., temporalOverlaps('2:55:00'.toTime, 1.hour, '3:30:00'.toTime, 2.hour) returns TRUE.

dateFormat(TIMESTAMP, STRING)

Returns a string that formats TIMESTAMP with a specified format STRING. The format specification is given in the Date Format Specifier table.

E.g., dateFormat(ts, '%Y, %d %M') results in strings formatted as "2017, 05 May".

timestampDiff(TIMEPOINTUNIT, TIMEPOINT1, TIMEPOINT2)

Returns the (signed) number of TIMEPOINTUNIT between TIMEPOINT1 and TIMEPOINT2. The unit for the interval is given by the first argument, which should be one of the following values: SECOND, MINUTE, HOUR, DAY, MONTH, or YEAR. See also the Time Interval and Point Unit Specifiers table.

E.g., timestampDiff(DAY, '2003-01-02 10:00:00'.toTimestamp, '2003-01-03 10:00:00'.toTimestamp) leads to 1.

Temporal functions Description
STRING.toDate

Returns a SQL date parsed from STRING in form of "yyyy-MM-dd".

STRING.toTime

Returns a SQL time parsed from STRING in form of "HH:mm:ss".

STRING.toTimestamp

Returns a SQL timestamp parsed from STRING in form of "yyyy-MM-dd HH:mm:ss[.SSS]".

NUMERIC.year
NUMERIC.years

Creates an interval of months for NUMERIC years.

NUMERIC.month
NUMERIC.months

Creates an interval of NUMERIC months.

NUMERIC.day
NUMERIC.days

Creates an interval of milliseconds for NUMERIC days.

NUMERIC.hour
NUMERIC.hours

Creates an interval of milliseconds for NUMERIC hours.

NUMERIC.minute
NUMERIC.minutes

Creates an interval of milliseconds for NUMERIC minutes.

NUMERIC.second
NUMERIC.seconds

Creates an interval of milliseconds for NUMERIC seconds.

NUMERIC.milli
NUMERIC.millis

Creates an interval of NUMERIC milliseconds.

currentDate()

Returns the current SQL date in the UTC time zone.

currentTime()

Returns the current SQL time in the UTC time zone.

currentTimestamp()

Returns the current SQL timestamp in the UTC time zone.

localTime()

Returns the current SQL time in local time zone.

localTimestamp()

Returns the current SQL timestamp in local time zone.

TEMPORAL.extract(TIMEINTERVALUNIT)

Returns a long value extracted from the TIMEINTERVALUNIT part of temporal.

E.g., "2006-06-05".toDate.extract(TimeIntervalUnit.DAY) returns 5; "2006-06-05".toDate.extract(QUARTER) returns 2.

TIMEPOINT.floor(TIMEINTERVALUNIT)

Returns a value that rounds TIMEPOINT down to the time unit TIMEINTERVALUNIT.

E.g., "12:44:31".toDate.floor(TimeIntervalUnit.MINUTE) returns 12:44:00.

TIMEPOINT.ceil(TIMEINTERVALUNIT)

Returns a value that rounds TIMEPOINT up to the time unit TIMEINTERVALUNIT.

E.g., "12:44:31".toTime.floor(TimeIntervalUnit.MINUTE) returns 12:45:00.

temporalOverlaps(TIMEPOINT1, TEMPORAL1, TIMEPOINT2, TEMPORAL2)

Returns TRUE if two time intervals defined by (TIMEPOINT1, TEMPORAL1) and (TIMEPOINT2, TEMPORAL2) overlap. The temporal values could be either a time point or a time interval.

E.g., temporalOverlaps("2:55:00".toTime, 1.hour, "3:30:00".toTime, 2.hour) returns TRUE.

dateFormat(TIMESTAMP, STRING)

Returns a string that formats TIMESTAMP with a specified format STRING. The format specification is given in the Date Format Specifier table.

E.g., dateFormat('ts, "%Y, %d %M") results in strings formatted as "2017, 05 May".

timestampDiff(TIMEPOINTUNIT, TIMEPOINT1, TIMEPOINT2)

Returns the (signed) number of TIMEPOINTUNIT between TIMEPOINT1 and TIMEPOINT2. The unit for the interval is given by the first argument, which should be one of the following values: SECOND, MINUTE, HOUR, DAY, MONTH, or YEAR. See also the Time Interval and Point Unit Specifiers table.

E.g., timestampDiff(TimePointUnit.DAY, '2003-01-02 10:00:00'.toTimestamp, '2003-01-03 10:00:00'.toTimestamp) leads to 1.

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Conditional Functions

Conditional functions Description
CASE value
WHEN value1_1 [, value1_2 ]* THEN result1
[ WHEN value2_1 [, value2_2 ]* THEN result2 ]*
[ ELSE resultZ ]
END

Returns resultX when the first time value is contained in (valueX_1, valueX_2, ...). When no value matches, returns resultZ if it is provided and returns NULL otherwise.

CASE
WHEN condition1 THEN result1
[ WHEN condition2 THEN result2 ]*
[ ELSE resultZ ]
END

Returns resultX when the first conditionX is met. When no condition is met, returns resultZ if it is provided and returns NULL otherwise.

NULLIF(value1, value2)

Returns NULL if value1 is equal to value2; returns value1 otherwise.

E.g., NULLIF(5, 5) returns NULL; NULLIF(5, 0) returns 5.

COALESCE(value1, value2 [, value3 ]* )

Returns the first value that is not NULL from value1, value2, ....

E.g., COALESCE(NULL, 5) returns 5.

Conditional functions Description
BOOLEAN.?(VALUE1, VALUE2)

Returns VALUE1 if BOOLEAN evaluates to TRUE; returns VALUE2 otherwise.

E.g., (42 > 5).?('A', 'B') returns "A".

Conditional functions Description
BOOLEAN.?(VALUE1, VALUE2)

Returns VALUE1 if BOOLEAN evaluates to TRUE; returns VALUE2 otherwise.

E.g., (42 > 5).?("A", "B") returns "A".

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Type Conversion Functions

Type conversion functions Description
CAST(value AS type)

Returns a new value being cast to type type. See the supported types here.

E.g., CAST('42' AS INT) returns 42; CAST(NULL AS VARCHAR) returns NULL of type VARCHAR.

Type conversion functions Description
ANY.cast(TYPE)

Returns a new ANY being cast to type TYPE. See the supported types here.

E.g., '42'.cast(INT) returns 42; Null(STRING) returns NULL of type STRING.

Type conversion functions Description
ANY.cast(TYPE)

Returns a new ANY being cast to type TYPE. See the supported types here.

E.g., "42".cast(Types.INT) returns 42; Null(Types.STRING) returns NULL of type STRING.

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Collection Functions

Collection functions Description
CARDINALITY(array)

Returns the number of elements in array.

array ‘[’ integer ‘]’

Returns the element at position integer in array. The index starts from 1.

ELEMENT(array)

Returns the sole element of array (whose cardinality should be one); returns NULL if array is empty. Throws an exception if array has more than one element.

CARDINALITY(map)

Returns the number of entries in map.

map ‘[’ value ‘]’

Returns the value specified by key value in map.

Collection functions Description
ARRAY.cardinality()

Returns the number of elements in ARRAY.

ARRAY.at(INT)

Returns the element at position INT in ARRAY. The index starts from 1.

ARRAY.element()

Returns the sole element of ARRAY (whose cardinality should be one); returns NULL if ARRAY is empty. Throws an exception if ARRAY has more than one element.

MAP.cardinality()

Returns the number of entries in MAP.

MAP.at(ANY)

Returns the value specified by key ANY in MAP.

Collection functions Description
ARRAY.cardinality()

Returns the number of elements in ARRAY.

ARRAY.at(INT)

Returns the element at position INT in ARRAY. The index starts from 1.

ARRAY.element()

Returns the sole element of ARRAY (whose cardinality should be one); returns NULL if ARRAY is empty. Throws an exception if ARRAY has more than one element.

MAP.cardinality()

Returns the number of entries in MAP.

MAP.at(ANY)

Returns the value specified by key ANY in MAP.

Value Construction Functions

Value construction functions Description
ROW(value1, [, value2]*)
(value1, [, value2]*)

Returns a row created from a list of values (value1, value2,...).

ARRAY ‘[’ value1 [, value2 ]* ‘]’

Returns an array created from a list of values (value1, value2, ...).

MAP ‘[’ value1, value2 [, value3, value4 ]* ‘]’

Returns a map created from a list of key-value pairs ((value1, value2), (value3, value4), ...).

Value constructor functions Description
row(ANY1, ANY2, ...)

Returns a row created from a list of object values (ANY1, ANY2, ...). Row is composite type that can be access via value access functions.

array(ANY1, ANY2, ...)

Returns an array created from a list of object values (ANY1, ANY2, ...).

map(ANY1, ANY2, ANY3, ANY4, ...)

Returns a map created from a list of key-value pairs ((ANY1, ANY2), (ANY3, ANY4), ...).

NUMERIC.rows

Creates a NUMERIC interval of rows (commonly used in window creation).

Value constructor functions Description
row(ANY1, ANY2, ...)

Returns a row created from a list of object values (ANY1, ANY2, ...). Row is composite type that can be access via value access functions.

array(ANY1, ANY2, ...)

Returns an array created from a list of object values (ANY1, ANY2, ...).

map(ANY1, ANY2, ANY3, ANY4, ...)

Returns a map created from a list of key-value pairs ((ANY1, ANY2), (ANY3, ANY4), ...).

NUMERIC.rows

Creates a NUMERIC interval of rows (commonly used in window creation).

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Value Access Functions

Value access functions Description
tableName.compositeType.field

Returns the value of a field from a Flink composite type (e.g., Tuple, POJO) by name.

tableName.compositeType.*

Returns a flat representation of a Flink composite type (e.g., Tuple, POJO) that converts each of its direct subtype into a separate field. In most cases the fields of the flat representation are named similarly to the original fields but with a dollar separator (e.g., mypojo$mytuple$f0).

Value access functions Description
COMPOSITE.get(STRING)
COMPOSITE.get(INT)

Returns the value of a field from a Flink composite type (e.g., Tuple, POJO) by name or index.

E.g., pojo.get('myField') or tuple.get(0).

ANY.flatten()

Returns a flat representation of a Flink composite type (e.g., Tuple, POJO) that converts each of its direct subtype into a separate field. In most cases the fields of the flat representation are named similarly to the original fields but with a dollar separator (e.g., mypojo$mytuple$f0).

Value access functions Description
COMPOSITE.get(STRING)
COMPOSITE.get(INT)

Returns the value of a field from a Flink composite type (e.g., Tuple, POJO) by name or index.

E.g., 'pojo.get("myField") or 'tuple.get(0).

ANY.flatten()

Returns a flat representation of a Flink composite type (e.g., Tuple, POJO) that converts each of its direct subtype into a separate field. In most cases the fields of the flat representation are named similarly to the original fields but with a dollar separator (e.g., mypojo$mytuple$f0).

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Grouping Functions

Grouping functions Description
GROUP_ID()

Returns an integer that uniquely identifies the combination of grouping keys.

GROUPING(expression1 [, expression2]* )
GROUPING_ID(expression1 [, expression2]* )

Returns a bit vector of the given grouping expressions.

Grouping functions Description
Grouping functions Description

Hash Functions

Hash functions Description
MD5(string)

Returns the MD5 hash of string as a string of 32 hexadecimal digits; returns NULL if string is NULL.

SHA1(string)

Returns the SHA-1 hash of string as a string of 40 hexadecimal digits; returns NULL if string is NULL.

SHA224(string)

Returns the SHA-224 hash of string as a string of 56 hexadecimal digits; returns NULL if string is NULL.

SHA256(string)

Returns the SHA-256 hash of string as a string of 64 hexadecimal digits; returns NULL if string is NULL.

SHA384(string)

Returns the SHA-384 hash of string as a string of 96 hexadecimal digits; returns NULL if string is NULL.

SHA512(string)

Returns the SHA-512 hash of string as a string of 128 hexadecimal digits; returns NULL if string is NULL.

SHA2(string, hashLength)

Returns the hash using the SHA-2 family of hash functions (SHA-224, SHA-256, SHA-384, or SHA-512). The first argument string is the string to be hashed and the second argument hashLength is the bit length of the result (224, 256, 384, or 512). Returns NULL if string or hashLength is NULL.

Hash functions Description
STRING.md5()

Returns the MD5 hash of STRING as a string of 32 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha1()

Returns the SHA-1 hash of STRING as a string of 40 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha224()

Returns the SHA-224 hash of STRING as a string of 56 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha256()

Returns the SHA-256 hash of STRING as a string of 64 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha384()

Returns the SHA-384 hash of STRING as a string of 96 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha512()

Returns the SHA-512 hash of STRING as a string of 128 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha2(INT)

Returns the SHA-2 family (SHA-224, SHA-256, SHA-384, or SHA-512) hashed value specified by INT (which could be 224, 256, 384, or 512) for STRING. Returns NULL if STRING or INT is NULL.

Hash functions Description
STRING.md5()

Returns the MD5 hash of STRING as a string of 32 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha1()

Returns the SHA-1 hash of STRING as a string of 40 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha224()

Returns the SHA-224 hash of STRING as a string of 56 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha256()

Returns the SHA-256 hash of STRING as a string of 64 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha384()

Returns the SHA-384 hash of STRING as a string of 96 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha512()

Returns the SHA-512 hash of STRING as a string of 128 hexadecimal digits; returns NULL if STRING is NULL.

STRING.sha2(INT)

Returns the SHA-2 family (SHA-224, SHA-256, SHA-384, or SHA-512) hashed value specified by INT (which could be 224, 256, 384, or 512) for STRING. Returns NULL if STRING or INT is NULL.

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Auxiliary Functions

Auxiliary functions Description
Auxiliary functions Description
ANY.as(NAME1, NAME2, ...)

Specifies a name for ANY (a field). Additional names can be specified if the expression expands to multiple fields.

Auxiliary functions Description
ANY.as(NAME1, NAME2, ...)

Specifies a name for ANY (a field). Additional names can be specified if the expression expands to multiple fields.

Aggregate Functions

The aggregate functions take an expression across all the rows as the input and return a single aggregated value as the result.

Aggregate functions Description
COUNT([ ALL ] expression | DISTINCT expression1 [, expression2]*)

By default or with ALL, returns the number of input rows for which expression is not NULL. Use DISTINCT for one unique instance of each value.

COUNT(*)
COUNT(1)

Returns the number of input rows.

AVG([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the average (arithmetic mean) of expression across all input rows. Use DISTINCT for one unique instance of each value.

SUM([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the sum of expression across all input rows. Use DISTINCT for one unique instance of each value.

MAX([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the maximum value of expression across all input rows. Use DISTINCT for one unique instance of each value.

MIN([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the minimum value of expression across all input rows. Use DISTINCT for one unique instance of each value.

STDDEV_POP([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the population standard deviation of expression across all input rows. Use DISTINCT for one unique instance of each value.

STDDEV_SAMP([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the sample standard deviation of expression across all input rows. Use DISTINCT for one unique instance of each value.

VAR_POP([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the population variance (square of the population standard deviation) of expression across all input rows. Use DISTINCT for one unique instance of each value.

VAR_SAMP([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns the sample variance (square of the sample standard deviation) of expression across all input rows. Use DISTINCT for one unique instance of each value.

COLLECT([ ALL | DISTINCT ] expression)

By default or with keyword ALL, returns a multiset of expression across all input rows. NULL values will be ignored. Use DISTINCT for one unique instance of each value.

Aggregate functions Description
FIELD.count

Returns the number of input rows for which FIELD is not NULL.

FIELD.avg

Returns the average (arithmetic mean) of FIELD across all input rows.

FIELD.sum

Returns the sum of numeric field FIELD across all input rows. If all values are NULL, returns NULL.

FIELD.sum0

Returns the sum of numeric field FIELD across all input rows. If all values are NULL, returns 0.

FIELD.max

Returns the maximum value of numeric field FIELD across all input rows.

FIELD.min

Returns the minimum value of numeric field FIELD across all input rows.

FIELD.stddevPop

Returns the population standard deviation of numeric field FIELD across all input rows.

FIELD.stddevSamp

Returns the sample standard deviation of numeric field FIELD across all input rows.

FIELD.varPop

Returns the population variance (square of the population standard deviation) of numeric field FIELD across all input rows.

FIELD.varSamp

Returns the sample variance (square of the sample standard deviation) of numeric field FIELD across all input rows.

FIELD.collect

Returns a multiset of FIELD across all input rows.

Aggregate functions Description
FIELD.count

Returns the number of input rows for which FIELD is not NULL.

FIELD.avg

Returns the average (arithmetic mean) of FIELD across all input rows.

FIELD.sum

Returns the sum of numeric field FIELD across all input rows. If all values are NULL, returns NULL.

FIELD.sum0

Returns the sum of numeric field FIELD across all input rows. If all values are NULL, returns 0.

FIELD.max

Returns the maximum value of numeric field FIELD across all input rows.

FIELD.min

Returns the minimum value of numeric field FIELD across all input rows.

FIELD.stddevPop

Returns the population standard deviation of numeric field FIELD across all input rows.

FIELD.stddevSamp

Returns the sample standard deviation of numeric field FIELD across all input rows.

FIELD.varPop

Returns the population variance (square of the population standard deviation) of numeric field FIELD across all input rows.

FIELD.varSamp

Returns the sample variance (square of the sample standard deviation) of numeric field FIELD across all input rows.

FIELD.collect

Returns a multiset of FIELD across all input rows.

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Date Format Specifiers

The following table lists specifiers for date format functions.

Specifier Description
%a
Abbreviated weekday name (Sun .. Sat)
%b
Abbreviated month name (Jan .. Dec)
%c
Month, numeric (1 .. 12)
%D
Day of the month with English suffix (0th, 1st, 2nd, 3rd, ...)
%d
Day of the month, numeric (01 .. 31)
%e
Day of the month, numeric (1 .. 31)
%f
Fraction of second (6 digits for printing: 000000 .. 999000; 1 - 9 digits for parsing: 0 .. 999999999) (Timestamp is truncated to milliseconds.)
%H
Hour (00 .. 23)
%h
Hour (01 .. 12)
%I
Hour (01 .. 12)
%i
Minutes, numeric (00 .. 59)
%j
Day of year (001 .. 366)
%k
Hour (0 .. 23)
%l
Hour (1 .. 12)
%M
Month name (January .. December)
%m
Month, numeric (01 .. 12)
%p
AM or PM
%r
Time, 12-hour (hh:mm:ss followed by AM or PM)
%S
Seconds (00 .. 59)
%s
Seconds (00 .. 59)
%T
Time, 24-hour (hh:mm:ss)
%U
Week (00 .. 53), where Sunday is the first day of the week
%u
Week (00 .. 53), where Monday is the first day of the week
%V
Week (01 .. 53), where Sunday is the first day of the week; used with %X
%v
Week (01 .. 53), where Monday is the first day of the week; used with %x
%W
Weekday name (Sunday .. Saturday)
%w
Day of the week (0 .. 6), where Sunday is the first day of the week
%X
Year for the week where Sunday is the first day of the week, numeric, four digits; used with %V
%x
Year for the week, where Monday is the first day of the week, numeric, four digits; used with %v
%Y
Year, numeric, four digits
%y
Year, numeric (two digits)
%%
A literal % character
%x
x, for any x not listed above

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Time Interval and Point Unit Specifiers

The following table lists specifiers for time interval and time point units.

For Table API, please use _ for spaces (e.g., DAY_TO_HOUR).

Time Interval Unit Time Point Unit
MILLENIUM (SQL-only)  
CENTURY (SQL-only)  
YEAR YEAR
YEAR TO MONTH  
QUARTER QUARTER
MONTH MONTH
WEEK WEEK
DAY DAY
DAY TO HOUR  
DAY TO MINUTE  
DAY TO SECOND  
HOUR HOUR
HOUR TO MINUTE  
HOUR TO SECOND  
MINUTE MINUTE
MINUTE TO SECOND  
SECOND SECOND
  MILLISECOND
  MICROSECOND
DOY (SQL-only)  
DOW (SQL-only)  
  SQL_TSI_YEAR (SQL-only)
  SQL_TSI_QUARTER (SQL-only)
  SQL_TSI_MONTH (SQL-only)
  SQL_TSI_WEEK (SQL-only)
  SQL_TSI_DAY (SQL-only)
  SQL_TSI_HOUR (SQL-only)
  SQL_TSI_MINUTE (SQL-only)
  SQL_TSI_SECOND (SQL-only)

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