Literals
A literal (also known as a constant) represents a fixed data value. Spark SQL supports the following literals:
- String Literal
- Binary Literal
- Null Literal
- Boolean Literal
- Numeric Literal
- Datetime Literal
- Interval Literal
String Literal
A string literal is used to specify a character string value.
Syntax
'char [ ... ]' | "char [ ... ]"
Parameters
-
char
One character from the character set. Use
\to escape special characters (e.g.,'or\).
Examples
SELECT 'Hello, World!' AS col;
+-------------+
| col|
+-------------+
|Hello, World!|
+-------------+
SELECT "SPARK SQL" AS col;
+---------+
| col|
+---------+
|Spark SQL|
+---------+
SELECT 'it\'s $10.' AS col;
+---------+
| col|
+---------+
|It's $10.|
+---------+
Binary Literal
A binary literal is used to specify a byte sequence value.
Syntax
X { 'num [ ... ]' | "num [ ... ]" }
Parameters
-
num
Any hexadecimal number from 0 to F.
Examples
SELECT X'123456' AS col;
+----------+
| col|
+----------+
|[12 34 56]|
+----------+
Null Literal
A null literal is used to specify a null value.
Syntax
NULL
Examples
SELECT NULL AS col;
+----+
| col|
+----+
|NULL|
+----+
Boolean Literal
A boolean literal is used to specify a boolean value.
Syntax
TRUE | FALSE
Examples
SELECT TRUE AS col;
+----+
| col|
+----+
|true|
+----+
Numeric Literal
A numeric literal is used to specify a fixed or floating-point number.
Integral Literal
Syntax
[ + | - ] digit [ ... ] [ L | S | Y ]
Parameters
-
digit
Any numeral from 0 to 9.
-
L
Case insensitive, indicates
BIGINT, which is an 8-byte signed integer number. -
S
Case insensitive, indicates
SMALLINT, which is a 2-byte signed integer number. -
Y
Case insensitive, indicates
TINYINT, which is a 1-byte signed integer number. -
default (no postfix)
Indicates a 4-byte signed integer number.
Examples
SELECT -2147483648 AS col;
+-----------+
| col|
+-----------+
|-2147483648|
+-----------+
SELECT 9223372036854775807l AS col;
+-------------------+
| col|
+-------------------+
|9223372036854775807|
+-------------------+
SELECT -32Y AS col;
+---+
|col|
+---+
|-32|
+---+
SELECT 482S AS col;
+---+
|col|
+---+
|482|
+---+
Fractional Literals
Syntax
decimal literals:
decimal_digits { [ BD ] | [ exponent BD ] } | digit [ ... ] [ exponent ] BD
double literals:
decimal_digits { D | exponent [ D ] } | digit [ ... ] { exponent [ D ] | [ exponent ] D }
While decimal_digits is defined as
[ + | - ] { digit [ ... ] . [ digit [ ... ] ] | . digit [ ... ] }
and exponent is defined as
E [ + | - ] digit [ ... ]
Parameters
-
digit
Any numeral from 0 to 9.
-
D
Case insensitive, indicates
DOUBLE, which is an 8-byte double-precision floating point number. -
BD
Case insensitive, indicates
DECIMAL, with the total number of digits as precision and the number of digits to right of decimal point as scale.
Examples
SELECT 12.578 AS col;
+------+
| col|
+------+
|12.578|
+------+
SELECT -0.1234567 AS col;
+----------+
| col|
+----------+
|-0.1234567|
+----------+
SELECT -.1234567 AS col;
+----------+
| col|
+----------+
|-0.1234567|
+----------+
SELECT 123. AS col;
+---+
|col|
+---+
|123|
+---+
SELECT 123.BD AS col;
+---+
|col|
+---+
|123|
+---+
SELECT 5E2 AS col;
+-----+
| col|
+-----+
|500.0|
+-----+
SELECT 5D AS col;
+---+
|col|
+---+
|5.0|
+---+
SELECT -5BD AS col;
+---+
|col|
+---+
| -5|
+---+
SELECT 12.578e-2d AS col;
+-------+
| col|
+-------+
|0.12578|
+-------+
SELECT -.1234567E+2BD AS col;
+---------+
| col|
+---------+
|-12.34567|
+---------+
SELECT +3.e+3 AS col;
+------+
| col|
+------+
|3000.0|
+------+
SELECT -3.E-3D AS col;
+------+
| col|
+------+
|-0.003|
+------+
Datetime Literal
A Datetime literal is used to specify a datetime value.
Date Literal
Syntax
DATE { 'yyyy' |
'yyyy-[m]m' |
'yyyy-[m]m-[d]d' |
'yyyy-[m]m-[d]d[T]' }
Note: defaults to 01 if month or day is not specified.
Examples
SELECT DATE '1997' AS col;
+----------+
| col|
+----------+
|1997-01-01|
+----------+
SELECT DATE '1997-01' AS col;
+----------+
| col|
+----------+
|1997-01-01|
+----------+
SELECT DATE '2011-11-11' AS col;
+----------+
| col|
+----------+
|2011-11-11|
+----------+
Timestamp Literal
Syntax
TIMESTAMP { 'yyyy' |
'yyyy-[m]m' |
'yyyy-[m]m-[d]d' |
'yyyy-[m]m-[d]d ' |
'yyyy-[m]m-[d]d[T][h]h[:]' |
'yyyy-[m]m-[d]d[T][h]h:[m]m[:]' |
'yyyy-[m]m-[d]d[T][h]h:[m]m:[s]s[.]' |
'yyyy-[m]m-[d]d[T][h]h:[m]m:[s]s.[ms][ms][ms][us][us][us][zone_id]'}
Note: defaults to 00 if hour, minute or second is not specified.
zone_id should have one of the forms:
- Z - Zulu time zone UTC+0
+|-[h]h:[m]m- An id with one of the prefixes UTC+, UTC-, GMT+, GMT-, UT+ or UT-, and a suffix in the formats:
+|-h[h]+|-hh[:]mm+|-hh:mm:ss+|-hhmmss
- Region-based zone IDs in the form
area/city, such asEurope/Paris
Note: defaults to the session local timezone (set via spark.sql.session.timeZone) if zone_id is not specified.
Examples
SELECT TIMESTAMP '1997-01-31 09:26:56.123' AS col;
+-----------------------+
| col|
+-----------------------+
|1997-01-31 09:26:56.123|
+-----------------------+
SELECT TIMESTAMP '1997-01-31 09:26:56.66666666UTC+08:00' AS col;
+--------------------------+
| col |
+--------------------------+
|1997-01-30 17:26:56.666666|
+--------------------------+
SELECT TIMESTAMP '1997-01' AS col;
+-------------------+
| col|
+-------------------+
|1997-01-01 00:00:00|
+-------------------+
Interval Literal
An interval literal is used to specify a fixed period of time.
INTERVAL interval_value interval_unit [ interval_value interval_unit ... ] |
INTERVAL 'interval_value interval_unit [ interval_value interval_unit ... ]' |
INTERVAL interval_string_value interval_unit TO interval_unit
Parameters
-
interval_value
Syntax:
[ + | - ] number_value | '[ + | - ] number_value' -
interval_string_value
year-month/day-time interval string.
-
interval_unit
Syntax:
YEAR[S] | MONTH[S] | WEEK[S] | DAY[S] | HOUR[S] | MINUTE[S] | SECOND[S] | MILLISECOND[S] | MICROSECOND[S]
Examples
SELECT INTERVAL 3 YEAR AS col;
+-------+
| col|
+-------+
|3 years|
+-------+
SELECT INTERVAL -2 HOUR '3' MINUTE AS col;
+--------------------+
| col|
+--------------------+
|-1 hours -57 minutes|
+--------------------+
SELECT INTERVAL '1 YEAR 2 DAYS 3 HOURS';
+----------------------+
| col|
+----------------------+
|1 years 2 days 3 hours|
+----------------------+
SELECT INTERVAL 1 YEARS 2 MONTH 3 WEEK 4 DAYS 5 HOUR 6 MINUTES 7 SECOND 8
MILLISECOND 9 MICROSECONDS AS col;
+-----------------------------------------------------------+
| col|
+-----------------------------------------------------------+
|1 years 2 months 25 days 5 hours 6 minutes 7.008009 seconds|
+-----------------------------------------------------------+
SELECT INTERVAL '2-3' YEAR TO MONTH AS col;
+----------------+
| col|
+----------------+
|2 years 3 months|
+----------------+
SELECT INTERVAL '20 15:40:32.99899999' DAY TO SECOND AS col;
+---------------------------------------------+
| col|
+---------------------------------------------+
|20 days 15 hours 40 minutes 32.998999 seconds|
+---------------------------------------------+