Equals

Returns true when both operands compare equal.

Category: comparison

SQL symbol: =

Syntax

sql

<left> = <right>

Parameters

<left> — The value to compare. Numeric types compare across the family, so 1 = 1.0 is true. Accepts boolean, date, decimal, float, integer, interval, nvarchar, timestamp, varbinary, varchar.
<right> — The value to compare it against. It must be type-compatible with the left - a number and a string are rejected rather than coerced. Accepts boolean, date, decimal, float, integer, interval, nvarchar, timestamp, varbinary, varchar.

Returns

boolean

Examples

sql

SELECT name FROM $planets WHERE name = 'Earth';

Earth

sql

SELECT 'Mars' = 'mars', 1 = 1.0, 1 = NULL;

false | true | NULL

Signatures

boolean = boolean → boolean
date = date → boolean
date = timestamp → boolean
decimal = decimal → boolean
decimal = float → boolean
decimal = integer → boolean
float = decimal → boolean
float = float → boolean
float = integer → boolean
integer = decimal → boolean
integer = float → boolean
integer = integer → boolean
interval = interval → boolean
nvarchar = nvarchar → boolean
nvarchar = varbinary → boolean
nvarchar = varchar → boolean
timestamp = date → boolean
timestamp = timestamp → boolean
varbinary = nvarchar → boolean
varbinary = varbinary → boolean
varbinary = varchar → boolean
varchar = nvarchar → boolean
varchar = varbinary → boolean
varchar = varchar → boolean

Notes

Comparison is three-valued: NULL on either side gives NULL, never true or false, and NULL = NULL is NULL too - IS NULL is the test for absence. String comparison is case-sensitive ('Mars' = 'mars' is false), unlike column NAMES, which are not.