How rigid is the max size of a VARCHAR in SQL Server?

Question

i.e. if I create a VARCHAR(50) field, what happens if I try to assign it a value that's 100 characters long?

Will SQL Server let me do this? Is it somehow less efficient?

Answer 1

If you try forcing a large string into a smaller-size variable, the incoming string will be simply chopped off at the appropriate size.

declare @Variable varchar (50)
set @Variable = replace (SPACE (100), ' ' , '.')
print @Variable 

the output is 50 characters long

..................................................

If you try to force a large string into a small sized Field in a Table, an Error will be raised

declare @MyTable Table
(
    TestVariable varchar (50)
)
insert into @MyTable (TestVariable) select replace (SPACE (100), ' ' , '.')
select * from @MyTable 

the output is

Msg 8152, Level 16, State 14, Line 6
String or binary data would be truncated.
The statement has been terminated.
TestVariable
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