SQL Case Sensitive String Compare

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How do you compare strings so that the comparison is true only if the cases of each of the strings are equal as well. For example:

Select * from a_table where attribute = 'k'

...will return a row with an attribute of 'K'. I do not want this behaviour.

6 Answers

simplifying the general answer

SQL Case Sensitive String Compare

These examples may be helpful:

Declare @S1 varchar(20) = 'SQL'
Declare @S2 varchar(20) = 'sql'

  
if @S1 = @S2 print 'equal!' else print 'NOT equal!' -- equal (default non-case sensitivity for SQL

if cast(@S1 as binary) = cast(Upper(@S2) as binary) print 'equal!' else print 'NOT equal!' -- equal

if cast(@S1 as binary) = cast(@S2 as binary) print 'equal!' else print 'NOT equal!' -- not equal

if  @S1 COLLATE Latin1_General_CS_AS  = Upper(@S2) COLLATE Latin1_General_CS_AS  print 'equal!' else print 'NOT equal!' -- equal

if  @S1 COLLATE Latin1_General_CS_AS  = @S2 COLLATE Latin1_General_CS_AS  print 'equal!' else print 'NOT equal!' -- not equal

 

The convert is probably more efficient than something like runtime calculation of hashbytes, and I'd expect the collate may be even faster.

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