functions.rst

Functions

Table of contents

• Introduction
• Type Conversion
  • CAST
• Mathematical Functions
  • ABS
  • ACOS
  • ADD
  • ASIN
  • ATAN
  • ATAN2
  • CBRT
  • CEIL
  • CONV
  • COS
  • COSH
  • COT
  • CRC32
  • DEGREES
  • DIVIDE
  • E
  • EXP
  • EXPM1
  • FLOOR
  • LN
  • LOG
  • LOG2
  • LOG10
  • MOD
  • MULTIPLY
  • PI
  • POW
  • POWER
  • RADIANS
  • RAND
  • RINT
  • ROUND
  • SIGN
  • SIGNUM
  • SIN
  • SINH
  • SQRT
  • STRCMP
  • SUBTRACT
  • TAN
  • TRUNCATE
• Date and Time Functions
  • ADDDATE
  • CURDATE
  • DATE
  • DATE_ADD
  • DATE_FORMAT
  • DATE_SUB
  • DAY
  • DAYNAME
  • DAYOFMONTH
  • DAYOFWEEK
  • DAYOFYEAR
  • FROM_DAYS
  • HOUR
  • MAKETIME
  • MICROSECOND
  • MINUTE
  • MONTH
  • MONTHNAME
  • NOW
  • QUARTER
  • SECOND
  • SUBDATE
  • TIME
  • TIME_TO_SEC
  • TIMESTAMP
  • TO_DAYS
  • WEEK
  • YEAR
• String Functions
  • ASCII
  • CONCAT
  • CONCAT_WS
  • LEFT
  • LENGTH
  • LOCATE
  • LOWER
  • LTRIM
  • REPLACE
  • RIGHT
  • RTRIM
  • SUBSTRING
  • TRIM
  • UPPER
• Conditional Functions
  • IF
  • IFNULL
  • ISNULL
  • CASE

Introduction

There is support for a wide variety of functions shared by SQL/PPL. We are intend to generate this part of documentation automatically from our type system. However, the type system is missing descriptive information for now. So only formal specifications of all functions supported are listed at the moment. More details will be added in future.

Most of the specifications can be self explained just as a regular function with data type as argument. The only notation that needs elaboration is generic type T which binds to an actual type and can be used as return type. For example, ABS(NUMBER T) -> T means function ABS accepts an numerical argument of type T which could be any sub-type of NUMBER type and returns the actual type of T as return type. The actual type binds to generic type at runtime dynamically.

Type Conversion

CAST

Description

Usage: cast(expr as dateType) cast the expr to dataType. return the value of dataType. The following conversion rules are used:

Src/Target	STRING	NUMBER	BOOLEAN	TIMESTAMP	DATE	TIME
STRING		Note1	Note1	TIMESTAMP()	DATE()	TIME()
NUMBER	Note1		v!=0	N/A	N/A	N/A
BOOLEAN	Note1	v?1:0		N/A	N/A	N/A
TIMESTAMP	Note1	N/A	N/A		DATE()	TIME()
DATE	Note1	N/A	N/A	N/A		N/A
TIME	Note1	N/A	N/A	N/A	N/A

Note1: the conversion follow the JDK specification.

Cast to string example:

od> SELECT cast(true as string) as cbool, cast(1 as string) as cint, cast(DATE '2012-08-07' as string) as cdate
fetched rows / total rows = 1/1
+---------+--------+------------+
| cbool   | cint   | cdate      |
|---------+--------+------------|
| true    | 1      | 2012-08-07 |
+---------+--------+------------+

Cast to number example:

od> SELECT cast(true as int) as cbool, cast('1' as int) as cstring
fetched rows / total rows = 1/1
+---------+-----------+
| cbool   | cstring   |
|---------+-----------|
| 1       | 1         |
+---------+-----------+

Cast to date example:

od> SELECT cast('2012-08-07' as date) as cdate, cast('01:01:01' as time) as ctime, cast('2012-08-07 01:01:01' as timestamp) as ctimestamp
fetched rows / total rows = 1/1
+------------+----------+---------------------+
| cdate      | ctime    | ctimestamp          |
|------------+----------+---------------------|
| 2012-08-07 | 01:01:01 | 2012-08-07 01:01:01 |
+------------+----------+---------------------+

Cast function can be chained:

od> SELECT cast(cast(true as string) as boolean) as cbool
fetched rows / total rows = 1/1
+---------+
| cbool   |
|---------|
| True    |
+---------+

Mathematical Functions

ABS

Description

Specifications:

1. ABS(NUMBER T) -> T

ACOS

Description

Usage: acos(x) calculate the arc cosine of x. Returns NULL if x is not in the range -1 to 1.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT ACOS(0)
fetched rows / total rows = 1/1
+--------------------+
| ACOS(0)            |
|--------------------|
| 1.5707963267948966 |
+--------------------+

ADD

Description

Specifications:

1. ADD(NUMBER T, NUMBER) -> T

ASIN

Description

Usage: asin(x) calculate the arc sine of x. Returns NULL if x is not in the range -1 to 1.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT ASIN(0)
fetched rows / total rows = 1/1
+-----------+
| ASIN(0)   |
|-----------|
| 0.0       |
+-----------+

ATAN

Description

Usage: atan(x) calculates the arc tangent of x. atan(y, x) calculates the arc tangent of y / x, except that the signs of both arguments are used to determine the quadrant of the result.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT ATAN(2), ATAN(2, 3)
fetched rows / total rows = 1/1
+--------------------+--------------------+
| ATAN(2)            | ATAN(2, 3)         |
|--------------------+--------------------|
| 1.1071487177940904 | 0.5880026035475675 |
+--------------------+--------------------+

ATAN2

Description

Usage: atan2(y, x) calculates the arc tangent of y / x, except that the signs of both arguments are used to determine the quadrant of the result.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT ATAN2(2, 3)
fetched rows / total rows = 1/1
+--------------------+
| ATAN2(2, 3)        |
|--------------------|
| 0.5880026035475675 |
+--------------------+

CBRT

Description

Specifications:

1. CBRT(NUMBER T) -> T

CEIL

Description

Specifications:

1. CEIL(NUMBER T) -> T

CONV

Description

Usage: CONV(x, a, b) converts the number x from a base to b base.

Argument type: x: STRING, a: INTEGER, b: INTEGER

Return type: STRING

Example:

od> SELECT CONV('12', 10, 16), CONV('2C', 16, 10), CONV(12, 10, 2), CONV(1111, 2, 10)
fetched rows / total rows = 1/1
+----------------------+----------------------+-------------------+---------------------+
| CONV('12', 10, 16)   | CONV('2C', 16, 10)   | CONV(12, 10, 2)   | CONV(1111, 2, 10)   |
|----------------------+----------------------+-------------------+---------------------|
| c                    | 44                   | 1100              | 15                  |
+----------------------+----------------------+-------------------+---------------------+

COS

Description

Usage: cos(x) calculate the cosine of x, where x is given in radians.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT COS(0)
fetched rows / total rows = 1/1
+----------+
| COS(0)   |
|----------|
| 1.0      |
+----------+

COSH

Description

Specifications:

1. COSH(NUMBER T) -> DOUBLE

COT

Description

Usage: cot(x) calculate the cotangent of x. Returns out-of-range error if x equals to 0.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT COT(1)
fetched rows / total rows = 1/1
+--------------------+
| COT(1)             |
|--------------------|
| 0.6420926159343306 |
+--------------------+

CRC32

Description

Usage: Calculates a cyclic redundancy check value and returns a 32-bit unsigned value.

Argument type: STRING

Return type: LONG

Example:

od> SELECT CRC32('MySQL')
fetched rows / total rows = 1/1
+------------------+
| CRC32('MySQL')   |
|------------------|
| 3259397556       |
+------------------+

DEGREES

Description

Usage: degrees(x) converts x from radians to degrees.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT DEGREES(1.57)
fetched rows / total rows  = 1/1
+-------------------+
| DEGREES(1.57)     |
|-------------------|
| 89.95437383553924 |
+-------------------+

DIVIDE

Description

Specifications:

1. DIVIDE(NUMBER T, NUMBER) -> T

E

Description

Usage: E() returns the Euler's number

Return type: DOUBLE

Example:

od> SELECT E()
fetched rows / total rows = 1/1
+-------------------+
| E()               |
|-------------------|
| 2.718281828459045 |
+-------------------+

EXP

Description

Specifications:

1. EXP(NUMBER T) -> T

EXPM1

Description

Specifications:

1. EXPM1(NUMBER T) -> T

FLOOR

Description

Specifications:

1. FLOOR(NUMBER T) -> T

LN

Description

Specifications:

1. LN(NUMBER T) -> DOUBLE

LOG

Description

Specifications:

1. LOG(NUMBER T) -> DOUBLE
2. LOG(NUMBER T, NUMBER) -> DOUBLE

LOG2

Description

Specifications:

1. LOG2(NUMBER T) -> DOUBLE

LOG10

Description

Specifications:

1. LOG10(NUMBER T) -> DOUBLE

MOD

Description

Usage: MOD(n, m) calculates the remainder of the number n divided by m.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: Wider type between types of n and m if m is nonzero value. If m equals to 0, then returns NULL.

Example:

od> SELECT MOD(3, 2), MOD(3.1, 2)
fetched rows / total rows = 1/1
+-------------+---------------+
| MOD(3, 2)   | MOD(3.1, 2)   |
|-------------+---------------|
| 1           | 1.1           |
+-------------+---------------+

MULTIPLY

Description

Specifications:

1. MULTIPLY(NUMBER T, NUMBER) -> NUMBER

PI

Description

Usage: PI() returns the constant pi

Return type: DOUBLE

Example:

od> SELECT PI()
fetched rows / total rows = 1/1
+-------------------+
| PI()              |
|-------------------|
| 3.141592653589793 |
+-------------------+

POW

Description

Usage: POW(x, y) calculates the value of x raised to the power of y. Bad inputs return NULL result.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Synonyms: POWER

Example:

od> SELECT POW(3, 2), POW(-3, 2), POW(3, -2)
fetched rows / total rows = 1/1
+-------------+--------------+--------------------+
| POW(3, 2)   | POW(-3, 2)   | POW(3, -2)         |
|-------------+--------------+--------------------|
| 9.0         | 9.0          | 0.1111111111111111 |
+-------------+--------------+--------------------+

POWER

Description

Usage: POWER(x, y) calculates the value of x raised to the power of y. Bad inputs return NULL result.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Synonyms: POW

Example:

od> SELECT POWER(3, 2), POWER(-3, 2), POWER(3, -2)
fetched rows / total rows = 1/1
+---------------+----------------+--------------------+
| POWER(3, 2)   | POWER(-3, 2)   | POWER(3, -2)       |
|---------------+----------------+--------------------|
| 9.0           | 9.0            | 0.1111111111111111 |
+---------------+----------------+--------------------+

RADIANS

Description

Usage: radians(x) converts x from degrees to radians.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT RADIANS(90)
fetched rows / total rows  = 1/1
+--------------------+
| RADIANS(90)        |
|--------------------|
| 1.5707963267948966 |
+--------------------+

RAND

Description

Usage: RAND()/RAND(N) returns a random floating-point value in the range 0 <= value < 1.0. If integer N is specified, the seed is initialized prior to execution. One implication of this behavior is with identical argument N, rand(N) returns the same value each time, and thus produces a repeatable sequence of column values.

Argument type: INTEGER

Return type: FLOAT

Example:

od> SELECT RAND(3)
fetched rows / total rows = 1/1
+------------+
| RAND(3)    |
|------------|
| 0.73105735 |
+------------+

RINT

Description

Specifications:

1. RINT(NUMBER T) -> T

ROUND

Description

Usage: ROUND(x, d) rounds the argument x to d decimal places, d defaults to 0 if not specified

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type map:

(INTEGER/LONG [,INTEGER]) -> LONG (FLOAT/DOUBLE [,INTEGER]) -> LONG

Example:

od> SELECT ROUND(12.34), ROUND(12.34, 1), ROUND(12.34, -1), ROUND(12, 1)
fetched rows / total rows = 1/1
+----------------+-------------------+--------------------+----------------+
| ROUND(12.34)   | ROUND(12.34, 1)   | ROUND(12.34, -1)   | ROUND(12, 1)   |
|----------------+-------------------+--------------------+----------------|
| 12.0           | 12.3              | 10.0               | 12             |
+----------------+-------------------+--------------------+----------------+

SIGN

Description

Usage: Returns the sign of the argument as -1, 0, or 1, depending on whether the number is negative, zero, or positive

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: INTEGER

Example:

od> SELECT SIGN(1), SIGN(0), SIGN(-1.1)
fetched rows / total rows = 1/1
+-----------+-----------+--------------+
| SIGN(1)   | SIGN(0)   | SIGN(-1.1)   |
|-----------+-----------+--------------|
| 1         | 0         | -1           |
+-----------+-----------+--------------+

SIGNUM

Description

Specifications:

1. SIGNUM(NUMBER T) -> T

SIN

Description

Usage: sin(x) calculate the sine of x, where x is given in radians.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT SIN(0)
fetched rows / total rows = 1/1
+----------+
| SIN(0)   |
|----------|
| 0.0      |
+----------+

SINH

Description

Specifications:

1. SINH(NUMBER T) -> DOUBLE

SQRT

Description

Usage: Calculates the square root of a non-negative number

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type map:

(Non-negative) INTEGER/LONG/FLOAT/DOUBLE -> DOUBLE (Negative) INTEGER/LONG/FLOAT/DOUBLE -> NULL

Example:

od> SELECT SQRT(4), SQRT(4.41)
fetched rows / total rows = 1/1
+-----------+--------------+
| SQRT(4)   | SQRT(4.41)   |
|-----------+--------------|
| 2.0       | 2.1          |
+-----------+--------------+

STRCMP

Description

Usage: strcmp(str1, str2) returns 0 if strings are same, -1 if first arg < second arg according to current sort order, and 1 otherwise.

Argument type: STRING, STRING

Return type: INTEGER

Example:

od> SELECT STRCMP('hello', 'world'), STRCMP('hello', 'hello')
fetched rows / total rows = 1/1
+----------------------------+----------------------------+
| STRCMP('hello', 'world')   | STRCMP('hello', 'hello')   |
|----------------------------+----------------------------|
| -1                         | 0                          |
+----------------------------+----------------------------+

SUBTRACT

Description

Specifications:

1. SUBTRACT(NUMBER T, NUMBER) -> T

TAN

Description

Usage: tan(x) calculate the tangent of x, where x is given in radians.

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type: DOUBLE

Example:

od> SELECT TAN(0)
fetched rows / total rows = 1/1
+----------+
| TAN(0)   |
|----------|
| 0.0      |
+----------+

TRUNCATE

Description

Usage: TRUNCATE(x, d) returns the number x, truncated to d decimal place

Argument type: INTEGER/LONG/FLOAT/DOUBLE

Return type map:

INTEGER/LONG -> LONG FLOAT/DOUBLE -> DOUBLE

Example:

fetched rows / total rows = 1/1
+----------------------+-----------------------+-------------------+
| TRUNCATE(56.78, 1)   | TRUNCATE(56.78, -1)   | TRUNCATE(56, 1)   |
|----------------------+-----------------------+-------------------|
| 56.7                 | 50                    | 56                |
+----------------------+-----------------------+-------------------+

Date and Time Functions

ADDDATE

Description

Usage: adddate(date, INTERVAL expr unit)/ adddate(date, expr) adds the time interval of second argument to date; adddate(date, days) adds the second argument as integer number of days to date.

Argument type: DATE/DATETIME/TIMESTAMP/STRING, INTERVAL/LONG

Return type map:

(DATE/DATETIME/TIMESTAMP/STRING, INTERVAL) -> DATETIME

(DATE, LONG) -> DATE

(DATETIME/TIMESTAMP/STRING, LONG) -> DATETIME

Synonyms: DATE_ADD

Example:

od> SELECT ADDDATE(DATE('2020-08-26'), INTERVAL 1 HOUR), ADDDATE(DATE('2020-08-26'), 1), ADDDATE(TIMESTAMP('2020-08-26 01:01:01'), 1)
fetched rows / total rows = 1/1
+------------------------------------------------+----------------------------------+------------------------------------------------+
| ADDDATE(DATE('2020-08-26'), INTERVAL 1 HOUR)   | ADDDATE(DATE('2020-08-26'), 1)   | ADDDATE(TIMESTAMP('2020-08-26 01:01:01'), 1)   |
|------------------------------------------------+----------------------------------+------------------------------------------------|
| 2020-08-26 01:00:00                            | 2020-08-27                       | 2020-08-27 01:01:01                            |
+------------------------------------------------+----------------------------------+------------------------------------------------+

CURDATE

Description

Specifications:

1. CURDATE() -> DATE

DATE

Description

Usage: date(expr) constructs a date type with the input string expr as a date. If the argument is of date/datetime/timestamp, it extracts the date value part from the expression.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: DATE

Example:

>od SELECT DATE('2020-08-26'), DATE(TIMESTAMP('2020-08-26 13:49:00'))
fetched rows / total rows = 1/1
+----------------------+------------------------------------------+
| DATE('2020-08-26')   | DATE(TIMESTAMP('2020-08-26 13:49:00'))   |
|----------------------+------------------------------------------|
| DATE '2020-08-26'    | DATE '2020-08-26'                        |
+----------------------+------------------------------------------+

DATE_ADD

Description

Usage: date_add(date, INTERVAL expr unit)/ date_add(date, expr) adds the time interval expr to date

Argument type: DATE/DATETIME/TIMESTAMP/STRING, INTERVAL/LONG

Return type map:

DATE/DATETIME/TIMESTAMP/STRING, INTERVAL -> DATETIME

DATE, LONG -> DATE

DATETIME/TIMESTAMP/STRING, LONG -> DATETIME

Synonyms: ADDDATE

Example:

od> SELECT DATE_ADD(DATE('2020-08-26'), INTERVAL 1 HOUR), DATE_ADD(DATE('2020-08-26'), 1), DATE_ADD(TIMESTAMP('2020-08-26 01:01:01'), 1)
fetched rows / total rows = 1/1
+-------------------------------------------------+-----------------------------------+-------------------------------------------------+
| DATE_ADD(DATE('2020-08-26'), INTERVAL 1 HOUR)   | DATE_ADD(DATE('2020-08-26'), 1)   | DATE_ADD(TIMESTAMP('2020-08-26 01:01:01'), 1)   |
|-------------------------------------------------+-----------------------------------+-------------------------------------------------|
| 2020-08-26 01:00:00                             | 2020-08-27                        | 2020-08-27 01:01:01                             |
+-------------------------------------------------+-----------------------------------+-------------------------------------------------+

DATE_FORMAT

Description

Usage: date_format(date, format) formats the date argument using the specifiers in the format argument.

The following table describes the available specifier arguments.

Specifier	Description
%a	Abbreviated weekday name (Sun..Sat)
%b	Abbreviated month name (Jan..Dec)
%c	Month, numeric (0..12)
%D	Day of the month with English suffix (0th, 1st, 2nd, 3rd, …)
%d	Day of the month, numeric (00..31)
%e	Day of the month, numeric (0..31)
%f	Microseconds (000000..999999)
%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 (00..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; WEEK() mode 0
%u	Week (00..53), where Monday is the first day of the week; WEEK() mode 1
%V	Week (01..53), where Sunday is the first day of the week; WEEK() mode 2; used with %X
%v	Week (01..53), where Monday is the first day of the week; WEEK() mode 3; used with %x
%W	Weekday name (Sunday..Saturday)
%w	Day of the week (0=Sunday..6=Saturday)
%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

Argument type: STRING/DATE/DATETIME/TIMESTAMP, STRING

Return type: STRING

Example:

>od SELECT DATE_FORMAT('1998-01-31 13:14:15.012345', '%T.%f'), DATE_FORMAT(TIMESTAMP('1998-01-31 13:14:15.012345'), '%Y-%b-%D %r')
fetched rows / total rows = 1/1
+-----------------------------------------------+----------------------------------------------------------------+
| DATE('1998-01-31 13:14:15.012345', '%T.%f')   | DATE(TIMESTAMP('1998-01-31 13:14:15.012345'), '%Y-%b-%D %r')   |
|-----------------------------------------------+----------------------------------------------------------------|
| '13:14:15.012345'                             | '1998-Jan-31st 01:14:15 PM'                                    |
+-----------------------------------------------+----------------------------------------------------------------+

DATE_SUB

Description

Usage: date_sub(date, INTERVAL expr unit)/ date_sub(date, expr) subtracts the time interval expr from date

Argument type: DATE/DATETIME/TIMESTAMP/STRING, INTERVAL/LONG

Return type map:

DATE/DATETIME/TIMESTAMP/STRING, INTERVAL -> DATETIME

DATE, LONG -> DATE

DATETIME/TIMESTAMP/STRING, LONG -> DATETIME

Synonyms: SUBDATE

Example:

od> SELECT DATE_SUB(DATE('2008-01-02'), INTERVAL 31 DAY), DATE_SUB(DATE('2020-08-26'), 1), DATE_SUB(TIMESTAMP('2020-08-26 01:01:01'), 1)
fetched rows / total rows = 1/1
+-------------------------------------------------+-----------------------------------+-------------------------------------------------+
| DATE_SUB(DATE('2008-01-02'), INTERVAL 31 DAY)   | DATE_SUB(DATE('2020-08-26'), 1)   | DATE_SUB(TIMESTAMP('2020-08-26 01:01:01'), 1)   |
|-------------------------------------------------+-----------------------------------+-------------------------------------------------|
| 2007-12-02                                      | 2020-08-25                        | 2020-08-25 01:01:01                             |
+-------------------------------------------------+-----------------------------------+-------------------------------------------------+

DAY

Description

Usage: day(date) extracts the day of the month for date, in the range 1 to 31. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Synonyms: DAYOFMONTH

Example:

od> SELECT DAY(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+---------------------------+
| DAY(DATE('2020-08-26'))   |
|---------------------------|
| 26                        |
+---------------------------+

DAYNAME

Description

Usage: dayname(date) returns the name of the weekday for date, including Monday, Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: STRING

Example:

od> SELECT DAYNAME(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+-------------------------------+
| DAYNAME(DATE('2020-08-26'))   |
|-------------------------------|
| Wednesday                     |
+-------------------------------+

DAYOFMONTH

Description

Usage: dayofmonth(date) extracts the day of the month for date, in the range 1 to 31. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Synonyms: DAY

Example:

od> SELECT DAYOFMONTH(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+----------------------------------+
| DAYOFMONTH(DATE('2020-08-26'))   |
|----------------------------------|
| 26                               |
+----------------------------------+

DAYOFWEEK

Description

Usage: dayofweek(date) returns the weekday index for date (1 = Sunday, 2 = Monday, …, 7 = Saturday).

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT DAYOFWEEK(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+---------------------------------+
| DAYOFWEEK(DATE('2020-08-26'))   |
|---------------------------------|
| 4                               |
+---------------------------------+

DAYOFYEAR

Description

Usage: dayofyear(date) returns the day of the year for date, in the range 1 to 366.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT DAYOFYEAR(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+---------------------------------+
| DAYOFYEAR(DATE('2020-08-26'))   |
|---------------------------------|
| 239                             |
+---------------------------------+

FROM_DAYS

Description

Usage: from_days(N) returns the date value given the day number N.

Argument type: INTEGER/LONG

Return type: DATE

Example:

od> SELECT FROM_DAYS(733687)
fetched rows / total rows = 1/1
+---------------------+
| FROM_DAYS(733687)   |
|---------------------|
| 2008-10-07          |
+---------------------+

HOUR

Description

Usage: hour(time) extracts the hour value for time. Different from the time of day value, the time value has a large range and can be greater than 23, so the return value of hour(time) can be also greater than 23.

Argument type: STRING/TIME/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT HOUR((TIME '01:02:03'))
fetched rows / total rows = 1/1
+---------------------------+
| HOUR((TIME '01:02:03'))   |
|---------------------------|
| 1                         |
+---------------------------+

MAKETIME

Description

Specifications:

1. MAKETIME(INTEGER, INTEGER, INTEGER) -> DATE

MICROSECOND

Description

Usage: microsecond(expr) returns the microseconds from the time or datetime expression expr as a number in the range from 0 to 999999.

Argument type: STRING/TIME/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT MICROSECOND((TIME '01:02:03.123456'))
fetched rows / total rows = 1/1
+-----------------------------------------+
| MICROSECOND((TIME '01:02:03.123456'))   |
|-----------------------------------------|
| 123456                                  |
+-----------------------------------------+

MINUTE

Description

Usage: minute(time) returns the minute for time, in the range 0 to 59.

Argument type: STRING/TIME/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT MINUTE((TIME '01:02:03'))
fetched rows / total rows = 1/1
+-----------------------------+
| MINUTE((TIME '01:02:03'))   |
|-----------------------------|
| 2                           |
+-----------------------------+

MONTH

Description

Usage: month(date) returns the month for date, in the range 1 to 12 for January to December. The dates with value 0 such as '0000-00-00' or '2008-00-00' are invalid.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT MONTH(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+-----------------------------+
| MONTH(DATE('2020-08-26'))   |
|-----------------------------|
| 8                           |
+-----------------------------+

MONTHNAME

Description

Usage: monthname(date) returns the full name of the month for date.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: STRING

Example:

od> SELECT MONTHNAME(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+---------------------------------+
| MONTHNAME(DATE('2020-08-26'))   |
|---------------------------------|
| August                          |
+---------------------------------+

NOW

Description

Specifications:

1. NOW() -> DATE

QUARTER

Description

Usage: quarter(date) returns the quarter of the year for date, in the range 1 to 4.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT QUARTER(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+-------------------------------+
| QUARTER(DATE('2020-08-26'))   |
|-------------------------------|
| 3                             |
+-------------------------------+

SECOND

Description

Usage: second(time) returns the second for time, in the range 0 to 59.

Argument type: STRING/TIME/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT SECOND((TIME '01:02:03'))
fetched rows / total rows = 1/1
+-----------------------------+
| SECOND((TIME '01:02:03'))   |
|-----------------------------|
| 3                           |
+-----------------------------+

SUBDATE

Description

Usage: subdate(date, INTERVAL expr unit)/ subdate(date, expr) subtracts the time interval expr from date

Argument type: DATE/DATETIME/TIMESTAMP/STRING, INTERVAL/LONG

Return type map:

DATE/DATETIME/TIMESTAMP/STRING, INTERVAL -> DATETIME

DATE, LONG -> DATE

DATETIME/TIMESTAMP/STRING, LONG -> DATETIME

Synonyms: DATE_SUB

Example:

od> SELECT SUBDATE(DATE('2008-01-02'), INTERVAL 31 DAY), SUBDATE(DATE('2020-08-26'), 1), SUBDATE(TIMESTAMP('2020-08-26 01:01:01'), 1)
fetched rows / total rows = 1/1
+------------------------------------------------+----------------------------------+------------------------------------------------+
| SUBDATE(DATE('2008-01-02'), INTERVAL 31 DAY)   | SUBDATE(DATE('2020-08-26'), 1)   | SUBDATE(TIMESTAMP('2020-08-26 01:01:01'), 1)   |
|------------------------------------------------+----------------------------------+------------------------------------------------|
| 2007-12-02                                     | 2020-08-25                       | 2020-08-25 01:01:01                            |
+------------------------------------------------+----------------------------------+------------------------------------------------+

TIME

Description

Usage: time(expr) constructs a time type with the input string expr as a time. If the argument is of date/datetime/time/timestamp, it extracts the time value part from the expression.

Argument type: STRING/DATE/DATETIME/TIME/TIMESTAMP

Return type: TIME

Example:

>od SELECT TIME('13:49:00'), TIME(TIMESTAMP('2020-08-26 13:49:00'))
fetched rows / total rows = 1/1
+--------------------+------------------------------------------+
| TIME('13:49:00')   | TIME(TIMESTAMP('2020-08-26 13:49:00'))   |
|--------------------+------------------------------------------|
| TIME '13:49:00'    | TIME '13:49:00'                          |
+--------------------+------------------------------------------+

TIME_TO_SEC

Description

Usage: time_to_sec(time) returns the time argument, converted to seconds.

Argument type: STRING/TIME/DATETIME/TIMESTAMP

Return type: LONG

Example:

od> SELECT TIME_TO_SEC(TIME '22:23:00')
fetched rows / total rows = 1/1
+--------------------------------+
| TIME_TO_SEC(TIME '22:23:00')   |
|--------------------------------|
| 80580                          |
+--------------------------------+

TIMESTAMP

Description

Usage: timestamp(expr) construct a timestamp type with the input string expr as an timestamp. If the argument is of date/datetime/timestamp type, cast expr to timestamp type with default timezone UTC.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: TIMESTAMP

Example:

>od SELECT TIMESTAMP('2020-08-26 13:49:00')
fetched rows / total rows = 1/1
+------------------------------------+
| TIMESTAMP('2020-08-26 13:49:00')   |
|------------------------------------|
| TIMESTAMP '2020-08-26 13:49:00     |
+------------------------------------+

TO_DAYS

Description

Usage: to_days(date) returns the day number (the number of days since year 0) of the given date. Returns NULL if date is invalid.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: LONG

Example:

od> SELECT TO_DAYS(DATE '2008-10-07')
fetched rows / total rows = 1/1
+------------------------------+
| TO_DAYS(DATE '2008-10-07')   |
|------------------------------|
| 733687                       |
+------------------------------+

WEEK

Description

Usage: week(date[, mode]) returns the week number for date. If the mode argument is omitted, the default mode 0 is used.

The following table describes how the mode argument works.

Mode	First day of week	Range	Week 1 is the first week …
0	Sunday	0-53	with a Sunday in this year
1	Monday	0-53	with 4 or more days this year
2	Sunday	1-53	with a Sunday in this year
3	Monday	1-53	with 4 or more days this year
4	Sunday	0-53	with 4 or more days this year
5	Monday	0-53	with a Monday in this year
6	Sunday	1-53	with 4 or more days this year
7	Monday	1-53	with a Monday in this year

Argument type: DATE/DATETIME/TIMESTAMP/STRING

Return type: INTEGER

Example:

>od SELECT WEEK(DATE('2008-02-20')), WEEK(DATE('2008-02-20'), 1)
fetched rows / total rows = 1/1
+----------------------------+-------------------------------+
| WEEK(DATE('2008-02-20'))   | WEEK(DATE('2008-02-20'), 1)   |
|----------------------------|-------------------------------|
| 7                          | 8                             |
+----------------------------+-------------------------------+

YEAR

Description

Usage: year(date) returns the year for date, in the range 1000 to 9999, or 0 for the “zero” date.

Argument type: STRING/DATE/DATETIME/TIMESTAMP

Return type: INTEGER

Example:

od> SELECT YEAR(DATE('2020-08-26'))
fetched rows / total rows = 1/1
+----------------------------+
| YEAR(DATE('2020-08-26'))   |
|----------------------------|
| 2020                       |
+----------------------------+

String Functions

ASCII

Description

Specifications:

1. ASCII(STRING T) -> INTEGER

CONCAT

Description

Usage: CONCAT(str1, str2) returns str1 and str strings concatenated together.

Argument type: STRING, STRING

Return type: STRING

Example:

od> SELECT CONCAT('hello', 'world')
fetched rows / total rows = 1/1
+----------------------------+
| CONCAT('hello', 'world')   |
|----------------------------|
| helloworld                 |
+----------------------------+

CONCAT_WS

Description

Usage: CONCAT_WS(sep, str1, str2) returns str1 concatenated with str2 using sep as a separator between them.

Argument type: STRING, STRING, STRING

Return type: STRING

Example:

od> SELECT CONCAT_WS(',', 'hello', 'world')
fetched rows / total rows = 1/1
+------------------------------------+
| CONCAT_WS(',', 'hello', 'world')   |
|------------------------------------|
| hello,world                        |
+------------------------------------+

LEFT

Description

Specifications:

1. LEFT(STRING T, INTEGER) -> T

LENGTH

Description

Specifications:

1. LENGTH(STRING) -> INTEGER

Usage: length(str) returns length of string measured in bytes.

Argument type: STRING

Return type: INTEGER

Example:

od> SELECT LENGTH('helloworld')
fetched rows / total rows = 1/1
+------------------------+
| LENGTH('helloworld')   |
|------------------------|
| 10                     |
+------------------------+

LOCATE

Description

Specifications:

1. LOCATE(STRING, STRING, INTEGER) -> INTEGER
2. LOCATE(STRING, STRING) -> INTEGER

LOWER

Description

Usage: lower(string) converts the string to lowercase.

Argument type: STRING

Return type: STRING

Example:

od> SELECT LOWER('helloworld'), LOWER('HELLOWORLD')
fetched rows / total rows = 1/1
+-----------------------+-----------------------+
| LOWER('helloworld')   | LOWER('HELLOWORLD')   |
|-----------------------+-----------------------|
| helloworld            | helloworld            |
+-----------------------+-----------------------+

LTRIM

Description

Usage: ltrim(str) trims leading space characters from the string.

Argument type: STRING

Return type: STRING

Example:

od> SELECT LTRIM('   hello'), LTRIM('hello   ')
fetched rows / total rows = 1/1
+---------------------+---------------------+
| LTRIM('   hello')   | LTRIM('hello   ')   |
|---------------------+---------------------|
| hello               | hello               |
+---------------------+---------------------+

REPLACE

Description

Specifications:

1. REPLACE(STRING T, STRING, STRING) -> T

RIGHT

Description

Usage: right(str, len) returns the rightmost len characters from the string str, or NULL if any argument is NULL.

Argument type: STRING, INTEGER

Return type: STRING

Example:

od> SELECT RIGHT('helloworld', 5), RIGHT('HELLOWORLD', 0)
fetched rows / total rows = 1/1
+--------------------------+--------------------------+
| RIGHT('helloworld', 5)   | RIGHT('HELLOWORLD', 0)   |
|--------------------------+--------------------------|
| world                    |                          |
+--------------------------+--------------------------+

RTRIM

Description

Usage: rtrim(str) trims trailing space characters from the string.

Argument type: STRING

Return type: STRING

Example:

od> SELECT RTRIM('   hello'), RTRIM('hello   ')
fetched rows / total rows = 1/1
+---------------------+---------------------+
| RTRIM('   hello')   | RTRIM('hello   ')   |
|---------------------+---------------------|
|    hello            | hello               |
+---------------------+---------------------+

SUBSTRING

Description

Usage: substring(str, start) or substring(str, start, length) returns substring using start and length. With no length, entire string from start is returned.

Argument type: STRING, INTEGER, INTEGER

Return type: STRING

Synonyms: SUBSTR

Example:

od> SELECT SUBSTRING('helloworld', 5), SUBSTRING('helloworld', 5, 3)
fetched rows / total rows = 1/1
+------------------------------+---------------------------------+
| SUBSTRING('helloworld', 5)   | SUBSTRING('helloworld', 5, 3)   |
|------------------------------+---------------------------------|
| oworld                       | owo                             |
+------------------------------+---------------------------------+

TRIM

Description

Argument Type: STRING

Return type: STRING

Example:

od> SELECT TRIM('   hello'), TRIM('hello   ')
fetched rows / total rows = 1/1
+--------------------+--------------------+
| TRIM('   hello')   | TRIM('hello   ')   |
|--------------------+--------------------|
| hello              | hello              |
+--------------------+--------------------+

UPPER

Description

Usage: upper(string) converts the string to uppercase.

Argument type: STRING

Return type: STRING

Example:

od> SELECT UPPER('helloworld'), UPPER('HELLOWORLD')
fetched rows / total rows = 1/1
+-----------------------+-----------------------+
| UPPER('helloworld')   | UPPER('HELLOWORLD')   |
|-----------------------+-----------------------|
| HELLOWORLD            | HELLOWORLD            |
+-----------------------+-----------------------+

Conditional Functions

IF

Description

Specifications:

1. IF(BOOLEAN, ES_TYPE, ES_TYPE) -> ES_TYPE

IFNULL

Description

Specifications:

1. IFNULL(ES_TYPE, ES_TYPE) -> ES_TYPE

ISNULL

Description

Specifications:

1. ISNULL(ES_TYPE) -> INTEGER

CASE

Description

CASE statement has two forms with slightly different syntax: Simple Case and Searched Case.

Simple case syntax compares a case value expression with each compare expression in WHEN clause and return its result if matched. Otherwise, result expression's value in ELSE clause is returned (or NULL if absent):

CASE case_value_expression
  WHEN compare_expression THEN result_expression
  [WHEN compare_expression THEN result_expression] ...
  [ELSE result_expression]
END

Similarly, searched case syntax evaluates each search condition and return result if true. A search condition must be a predicate that returns a bool when evaluated:

CASE
  WHEN search_condition THEN result_expression
  [WHEN search_condition THEN result_expression] ...
  [ELSE result_expression]
END

Type Check

All result types in WHEN and ELSE clause are required to be exactly the same. Otherwise, take the following query for example, you'll see an semantic analysis exception thrown:

CASE age
  WHEN 30 THEN 'Thirty'
  WHEN 50 THEN true
END

Examples

Here are examples for simple case syntax:

od> SELECT
...   CASE 1
...     WHEN 1 THEN 'One'
...   END AS simple_case,
...   CASE ABS(-2)
...     WHEN 1 THEN 'One'
...     WHEN 2 THEN 'Absolute two'
...   END AS func_case_value,
...   CASE ABS(-3)
...     WHEN 1 THEN 'One'
...     ELSE TRIM(' Absolute three ')
...   END AS func_result;
fetched rows / total rows = 1/1
+---------------+-------------------+----------------+
| simple_case   | func_case_value   | func_result    |
|---------------+-------------------+----------------|
| One           | Absolute two      | Absolute three |
+---------------+-------------------+----------------+

Here are examples for searched case syntax:

od> SELECT
...   CASE
...     WHEN 1 = 1 THEN 'One'
...   END AS single_search,
...   CASE
...     WHEN 2 = 1 THEN 'One'
...     WHEN 'hello' = 'hello' THEN 'Hello' END AS multi_searches,
...   CASE
...     WHEN 2 = 1 THEN 'One'
...     WHEN 'hello' = 'world' THEN 'Hello'
...   END AS no_else;
fetched rows / total rows = 1/1
+-----------------+------------------+-----------+
| single_search   | multi_searches   | no_else   |
|-----------------+------------------+-----------|
| One             | Hello            | null      |
+-----------------+------------------+-----------+