Rows disappearing despite LEFT JOIN? Verifying the difference between WHERE and ON with 3 data records

"I thought LEFT JOIN would keep the data on the left, but the number of records decreased when I added WHERE."When creating ...

5 Points to Check First When SQL Is Slow: How to Improve Execution Plans, Indexes, and JOINs

When you execute an SQL query, the results do not return quickly.You may have had no issues during development, but the ...
techtarget

Using a LEFT OUTER JOIN vs. RIGHT OUTER JOIN in SQL

In this excerpt from SQL Queries for Mere Mortals: A Hands-On Guide to Data Manipulation in SQL, John L. Viescas and Michael J. Hernandez discuss the LEFT OUTER JOIN vs. the RIGHT OUTER JOIN and offer ...
Ars Technica

SQL - Joining two databases

I am trying to join two databases in an SQL query. Database A has a table with a 5 digit client number and another table with a 5 digit matter number. The other database, B, has a table with one field ...
TechRepublic

Understand the effects of NULLs on inner and outer JOINs

In this SQL Server tip, Arthur Fuller explains the effects of NULLs, and the different results obtained by inner and outer JOINs. SQL Server developers must understand two things: the difference ...