October 2002
Beginner
864 pages
18h 41m
English
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Preventing Problems with Your Data
Your data processing center should have a backup system set up. If your database is small to medium, you can take the extra precaution of using EXPORT to ensure that your data is backed up. You should make a backup of the export file and keep it in another location for further safety. Remember that these files can be large and will require a great deal of space.
Searching for Duplicate Records in Your Database
If your database is perfectly planned, you should not have a problem with duplicate records. You can avoid duplicate records by using constraints, foreign keys, and unique indexes. See Day 10, “Controlling Data Integrity,” for more information on constraints, foreign keys, and unique indexes.
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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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