How can use alter table column and add constraint in single query in SQL Server 2012

Question

In MySQL I use:

alter table (table name)
    modify column name varchar(255) not null unique

How to use same query in SQL Server?

Thank you

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score 3 · Answer 1 · answered Oct 10 '18 at 08:05

I have not tested this. For SQL Server 2008 and above:

ALTER TABLE table_name
  ALTER COLUMN column_name varchar(255) not null;

Apparently, the unique constraint cannot be on the same command, so.. no, you can't put that in a single query:

ALTER TABLE table_name
  ADD CONSTRAINT constraint_name UNIQUE(column_name);

Change the table_name, column_name and constraint_name accordingly.

1 Answers1