How to find out whether a table has some unique columns

Question

I use MS SQL Server.

Ive been handed some large tables with no constrains on them, no keys no nothing.

I know some of the columns have unique values. Is ther

Answer 1

What about simple one line of code:

CREATE UNIQUE INDEX index_name ON table_name (column_name);

If the index is created then your column_name has only unique values. If there are dupes in your column_name, you will get an error message.