In SQL Server, what does “SET ANSI_NULLS ON” mean?

Question

The definition says:

When SET ANSI_NULLS is ON, a SELECT statement that uses WHERE column_name = NULL returns zero rows even if there are null values

Answer 1

I guess the main thing here is:

Never user:

• @anything = NULL
• @anything <> NULL
• @anything != null

Always use:

• @anything IS NULL
• @anything IS NOT NULL