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9.3.11     MySQL for dummies

This is NOT the latest copy of this book; click here for the latest version.

Now that you have learnt how to update and delete records in your table, it is only really a matter of time until you issue your first query like this:

UPDATE usertable SET FirstName = 'Bob';

Then realise you meant to add "WHERE FirstName = 'Robert'" at the end. Instead of changing Robert to Bob, your query will also change Peter, James, Sally, and anyone else in the database to Bob - a disaster!

To work around this, the MySQL monitor has a special command line option, --i-am-a-dummy (seriously), that will, amongst other things, not allow you to execute any UPDATE or DELETE statements without a WHERE clause. This might sound a bit extreme, but you will be thankful for it if you issue wrong queries regularly!





<< 9.3.10 Deleting data   9.3.12 A working example >>
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