sql insert into table from select without duplicates (need more then a DISTINCT)

Question

I am selecting multiple rows and inserting them into another table. I want to make sure that it doesn\'t already exists in the table I am inserting multiple rows into.

Answer 1

So you're looking to retrieve all unique rows from source table which do not already exist in target table?

SELECT DISTINCT(*) FROM source
WHERE primaryKey NOT IN (SELECT primaryKey FROM target)

That's assuming you have a primary key which you can base the uniqueness on... otherwise, you'll have to check each column for uniqueness.