UNION and UNION ALL are both used to retrieve records from multiple tables. This article will detail the differences between the two, allowing you to make the best choice for each unique scenario. You can use SQL’s UNION and UNION ALL commands to get data from multiple tables in […]

What Is a CTE? CTE is defined as a Common Table Expression. You create a CTE using a WITH query, then reference it within a SELECT, INSERT, UPDATE, or DELETE statement. It goes by a few names: Common Table Expression Subquery Factoring SQL WITH Clause […]

One of the greatest challenges in writing queries is deciding which to use, whether to use joins or sub-queries. The truth is that they vary, there are situations that subquery is best to use and there are some situations that join is the best option. […]