October 2002
Beginner
864 pages
18h 41m
English
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Disabling Table Constraints to Load Data
When loading data into tables, you will sometimes have to disable the constraints on your tables. Suppose that you have truncated your tables and you are loading data into your tables from scratch. More than likely, your tables will have referential integrity constraints, such as foreign keys. Because the database will not let you insert a row of data in a table that references another table (if the referenced column does not exist in the other table), you may have to disable constraints to initially load your data. Of course, after the load is successful, you would want to enable the constraints.
SQL> SET ECHO OFF SQL> SET FEEDBACK OFF SQL> SET HEADING OFF SQL> SPOOL DISABLE.SQL SQL> SELECT 'ALTER TABLE ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
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.