Introducing the SQL commands that allow us to perform relatively complex set operations on a database.
As with the other topics we’ve covered in this series, there is a wealth of information available on the topic of sets, databases, and SQL.
We'll get into the following topics in this stage, but here are a few links that talk a little more about Set Operations in SQL:
- What is the difference between a JOIN and a UNION?
- Learn to use UNION, INTERSECT, and EXCEPT Clauses
Other good reads about Set Operations include:
Union and Union All:
[MUSIC] 0:00 In our last stage, 0:04 we learned how to merge dates together from two different tables with SQL Joins. 0:05 In this stage, we're going to learn about set operations. 0:10 Set operations allow you to perform different tasks on separate tables or 0:15 datasets. 0:19 You can use these operations to combine two or 0:20 more datasets into one in various ways or to limit the results of one with another. 0:23 There are four set operations, Union, Union All, Intersect and Except. 0:29 Union and Union All combine data from multiple tables into one result set. 0:36 Intersect produces a result set from values of rows that's are in common 0:41 between both tables. 0:46 And except produces a result set of values of rows that exist in the first table, 0:47 but not the second. 0:53 Will be taking a look at these set operations in more detail in this stage. 0:55
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