SQL Server : allow 3 letters and 4 numbers in a varchar(7) column

Question

I'm trying to create a constraint for a SQL Server table in order to allow only 3 letters and 4 numbers on a single varchar(7) column.

Example: ABC1234

Can anyone help?

Answer 1

You could use:

ALTER TABLE tab_name ADD CONSTRAINT
constraint_name CHECK (col LIKE '[A-Z][A-Z][A-Z][0-9][0-9][0-9][0-9]');

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