SQL Server is an ocean of information. I believe if one starts learning today, after 60 years he/she may still be learning the subject (there are always a few exceptions)! Recently, I published the SQL Server Questions and Answers video tutorial, and since the course came out, I have been receiving lots of request to share SQL Tips which are small and easy to digest.
While writing the SQL books with my co-authors Vinod Kumar and Rick Morelan, we often came across very interesting and useful tips which we believe would be helpful to readers. Sometimes the tips are so small that we could not find an appropriate place for them in the book. We call them Sixty Seconds Tips. The tips are so small that sometimes sixty seconds are too long for them. Keeping the notion of quick and easy tips – we have decided to come up with new series called “SQL in Sixty Seconds.” Every week we will post one small but useful video tip. We believe that Sixty Seconds is metaphor for quick and easy tip.
I have seen many developers staying away from CTE (Common Table Expression), their excuse is that they do not know how to convert subqueries to CTE or they think it is very complicated to do so. In the very first episode of SQL in Sixty Seconds we will see how easily one can convert Subqueries to CTE and CTE to Subqueries.
More on CTE:
Simple Example of Recursive CTE
Multiple CTE in One SELECT Statement Query
Common Table Expression (CTE) and Few Observation
Delete Duplicate Rows
Simple Example of Recursive CTE – Part 2 – MAXRECURSION – Prevent CTE Infinite Loop
T-SQL Paging Query Technique Comparison (OVER and ROW_NUMBER()) – CTE vs. Derived Table
I encourage you to submit your ideas for SQL in Sixty Seconds. We will try to accommodate as many as we can.
Reference: Pinal Dave (https://blog.sqlauthority.com)