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Editorial Team
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Asked: 2026-06-10T20:56:33+00:00

For example, if I have this data: CREATE TABLE FooBar ( Name varchar(16) )

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For example, if I have this data:

CREATE TABLE FooBar ( Name varchar(16) )

INSERT FooBar SELECT 'test@test.com'

The following queries don’t return what I would expect:

SELECT * FROM FooBar WHERE Name = 'test@test.com       '  -- Returns the row

SELECT * FROM FooBar WHERE Name LIKE 'test@test.com '  -- Nothing Returned

SELECT * FROM FooBar WHERE Name = ' test@test.com' -- Nothing Returned

Why does = (which I assume means exactly equals) with extra space at the end return data, while a LIKE does not?

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1 Answer

  1. Editorial Team

    Seing the standard it depends on padding (The ANSI standard requires padding for the character strings used in comparisons so that their lengths match before comparing them)

    SQL Server follows the ANSI/ISO SQL-92 specification (Section 8.2, ,
    General rules #3) on how to compare strings with spaces. The ANSI
    standard requires padding for the character strings used in
    comparisons so that their lengths match before comparing them. The
    padding directly affects the semantics of WHERE and HAVING clause
    predicates and other Transact-SQL string comparisons. For example,
    Transact-SQL considers the strings ‘abc’ and ‘abc ‘ to be equivalent
    for most comparison operations.

    The only exception to this rule is the LIKE predicate. When the right
    side of a LIKE predicate expression features a value with a trailing
    space, SQL Server does not pad the two values to the same length
    before the comparison occurs. Because the purpose of the LIKE
    predicate, by definition, is to facilitate pattern searches rather
    than simple string equality tests, this does not violate the section
    of the ANSI SQL-92 specification mentioned earlier.

    See also how SQL Server compares strings with trailing spaces

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