Learn how to optimize SQL queries for NULL values by following some best practices and techniques, such as using IS NULL or IS NOT NULL operators, avoiding NOT IN with NULL values, and more.

The lack of information within relational databases expressed as NULL values presents a problem in ensuring the quality of data and the information retrieved by SQL queries. This is so because there ...

IS NULL and IS MISSING are predicates that test for a missing value. IS NULL and IS MISSING are used in the WHERE, ON, and HAVING expressions. Each predicate resolves to true if the sql-expression's ...

This transformation may seem to be a waste of effort because, at the end of the day, a value that means “null” simply replaces any null. The difference is that the meaning of null is still conveyed ...