October 2002
Beginner
864 pages
18h 41m
English
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Arranging Elements in a Query
The best arrangement of elements within your query, particularly in the WHERE clause, really depends on the order of the processing steps in a specific implementation. The arrangement of conditions depends on the columns that are indexed, as well as on which condition will retrieve the fewest records.
You do not have to use a column that is indexed in the WHERE clause, but it is obviously more beneficial to do so. Try to narrow down the results of the SQL statement by using an index that returns the fewest number of rows. If you recall, the condition that returns the fewest records in a table is said to be the most restrictive condition. As a general statement, you should place the most restrictive conditions last ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.