Project: Apache Spark (App Definition and Development / Streaming & Messaging)
File: sql-ref-literals.md

layout: global title: Literals displayTitle: Literals license: | Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. A literal (also known as a constant) represents a fixed data value. Spark SQL supports the following literals: * * * A string literal is used to specify a character string value. ```sql [ r ] { 'char [ ... ]' | "char [ ... ]" } ``` char* One character from the character set. Use `\` to escape special characters (e.g., `'` or `\`). To represent unicode characters, use 16-bit or 32-bit unicode escape of the form `\uxxxx` or `\Uxxxxxxxx`, where xxxx and xxxxxxxx are 16-bit and 32-bit code points in hexadecimal respectively (e.g., `\u3042` for `` and `\U0001F44D` for ``). r* Case insensitive, indicates `RAW`. If a string literal starts with `r` prefix, neither special characters nor unicode characters are escaped by `\`. The following escape sequences are recognized in regular string literals (without the `r` prefix), and replaced according to the following rules: `\0` -> `\u0000`, unicode character with the code 0; `\b` -> `\u0008`, backspace; `\n` -> `\u000a`, linefeed; `\r` -> `\u000d`, carriage return; `\t` -> `\u0009`, horizontal tab; `\Z` -> `\u001A`, substitute; `\%` -> `\%`; `\` -> `\`; `\<other char>` -> `<other char>`, skip the slash and leave the character as is. The unescaping rules above can be turned off by setting the SQL config `spark.sql.parser.escapedStringLiterals` to `true`. ```sql 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.| ++ SELECT r"'\n' represents newline character." AS col; +-+ | col| +-+ |'\n' represents newline character.| +-+ ``` A binary literal is used to specify a byte sequence value. ```sql X { 'num [ ... ]' | "num [ ... ]" } ``` num* Any hexadecimal number from 0 to F. ```sql SELECT X'123456' AS col; +-+ | col| +-+ |[12 34 56]| +-+ ``` A null literal is used to specify a null value. ```sql NULL ``` ```sql SELECT NULL AS col; +-+ | col| +-+ |NULL| +-+ ``` A boolean literal is used to specify a boolean value. ```sql TRUE | FALSE ``` ```sql SELECT TRUE AS col; +-+ | col| +-+ |true| +-+ ``` A numeric literal is used to specify a fixed or floating-point number. There are two kinds of numeric literals: integral literal and fractional literal. ```sql [ + | - ] digit [ ... ] [ L | S | Y ] ``` digit* Any numeral from 0 to 9. L* Case insensitive, indicates `BIGINT`, which is an 8-byte signed integer

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. ```sql SELECT -2147483648 AS col; +--+ | col| +--+ |-2147483648| +--+ SELECT 9223372036854775807l AS col; +-+ | col| +-+ |9223372036854775807| +-+ SELECT -32Y AS col; ++ |col| ++ |-32| ++ SELECT 482S AS col; ++ |col| ++ |482| ++ ``` decimal literals: ```sql decimal_digits { [ BD ] | [ exponent BD ] } | digit [ ... ] [ exponent ] BD ``` double literals: ```sql decimal_digits { D | exponent [ D ] } | digit [ ... ] { exponent [ D ] | [ exponent ] D } ``` float literals: ```sql decimal_digits { F | exponent [ F ] } | digit [ ... ] { exponent [ F ] | [ exponent ] F } ``` While decimal_digits is defined as ```sql [ + | - ] { digit [ ... ] . [ digit [ ... ] ] | . digit [ ... ] } ``` and exponent is defined as ```sql E [ + | - ] digit [ ... ] ``` digit* Any numeral from 0 to 9. D* Case insensitive, indicates `DOUBLE`, which is an 8-byte double-precision floating point number. F* Case insensitive, indicates `FLOAT`, which is a 4-byte single-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. ```sql SELECT 12.578 AS col, TYPEOF(12.578) AS type; +++ | col| type| +++ |12.578|decimal(5,3)| +++ SELECT 12.578E0 AS col, TYPEOF(12.578E0) AS type; +++ | col| type| +++ |12.578|double| +++ 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| ++ ``` A datetime literal is used to specify a date or timestamp value. ```sql 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. ```sql 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| +-+ ``` ```sql TIMESTAMP { 'yyyy' | 'yyyy-[m]m' | 'yyyy-[m]m-[d]d' | 'yyyy-[m]m-[d]d ' | 'yyyy-h[:]' | 'yyyy-h:[m]m[:]' | 'yyyy-h:[m]m:[s]s[.]' | 'yyyy-h:[zone_id]'} ``` Note: defaults to `00` if hour, minute or second is not

`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 as `Europe/Paris` Note: defaults to the session local timezone (set via `spark.sql.session.timeZone`) if `zone_id` is not specified. ```sql 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| +-+ ``` An interval literal is used to specify a fixed period of time. The interval literal supports two syntaxes: ANSI syntax and multi-units syntax. The ANSI SQL standard defines interval literals in the form: ```sql INTERVAL [ <sign> ] <interval string> <interval qualifier> ``` where `<interval qualifier>` can be a single field or in the field-to-field form: ```sql <interval qualifier> ::= <start field> TO <end field> | <single field> ``` The field name is case-insensitive, and can be one of `YEAR`, `MONTH`, `DAY`, `HOUR`, `MINUTE` and `SECOND`. An interval literal can have either year-month or day-time interval type. The interval sub-type defines format of `<interval string>`: ```sql <interval string> ::= <quote> [ <sign> ] { <year-month literal> | <day-time literal> } <quote> <year-month literal> ::= <years value> [ <minus sign> <months value> ] | <months value> <day-time literal> ::= <day-time interval> | <time interval> <day-time interval> ::= <days value> [ <space> <hours value> [ <colon> <minutes value> [ <colon> <seconds value> ] ] ] <time interval> ::= <hours value> [ <colon> <minutes value> [ <colon> <seconds value> ] ] | <minutes value> [ <colon> <seconds value> ] | <seconds value> ``` Supported year-month interval literals and theirs formats: |`<interval qualifier>`|Interval string pattern|An instance of the literal| ||-|| |YEAR|`[+|-]'[+|-]y'`|`INTERVAL -'2021' YEAR`| |YEAR TO MONTH|`[+|-]'[+|-]y-m'`|`INTERVAL '-2021-07' YEAR TO MONTH`| |MONTH|`[+|-]'[+|-]m'`|`interval '10' month`| Formats of supported day-time interval literals: |`<interval qualifier>`|Interval string pattern|An instance of the literal| ||-|-| |DAY|`[+|-]'[+|-]d'`|`INTERVAL -'100' DAY`| |DAY TO HOUR|`[+|-]'[+|-]d h'`|`INTERVAL '-100 10' DAY TO HOUR`| |DAY TO MINUTE|`[+|-]'[+|-]d h:m'`|`INTERVAL '100 10:30' DAY TO MINUTE`| |DAY TO SECOND|`[+|-]'[+|-]d h:m:s.n'`|`INTERVAL '100 10:30:40.999999' DAY TO SECOND`| |HOUR|`[+|-]'[+|-]h'`|`INTERVAL '123' HOUR`| |HOUR TO MINUTE|`[+|-]'[+|-]h:m'`|`INTERVAL -'-123:10' HOUR TO MINUTE`| |HOUR TO SECOND|`[+|-]'[+|-]h:m:s.n'`|`INTERVAL '123:10:59' HOUR TO SECOND`| |MINUTE|`[+|-]'[+|-]m'`|`interval '1000' minute`| |MINUTE TO SECOND|`[+|-]'[+|-]m:s.n'`|`INTERVAL '1000:01.001' MINUTE TO SECOND`| |SECOND|`[+|-]'[+|-]s.n'`|`INTERVAL '1000.000001' SECOND`| ```sql SELECT INTERVAL '2-3' YEAR TO MONTH AS col; +-+ |col | +-+ |INTERVAL '2-3' YEAR TO MONTH| +-+ SELECT INTERVAL -'20 15:40:32.99899999' DAY TO SECOND AS col; +--+ |col | +--+ |INTERVAL '-20 15:40:32.998999' DAY TO SECOND| +--+ ``` ```sql INTERVAL intervalvalue intervalunit [ intervalvalue intervalunit ... ] | INTERVAL 'intervalvalue intervalunit [ intervalvalue intervalunit ... ]' | ``` interval_value* Syntax: [ + | - ] numbervalue | '[ + | - ] numbervalue' interval_unit* Syntax: YEAR[S] | MONTH[S] | WEEK[S] | DAY[S] | HOUR[S] | MINUTE[S] | SECOND[S] | MILLISECOND[S] | MICROSECOND[S] Mix of the YEAR[S] or MONTH[S] interval units with other units is not allowed. ```sql 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| +--+ ```