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Triggers |
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rev. 19/10/2010
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Triggers |
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rev. 19/10/2010
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Triggers are SQL Server objects that are attached to a table. They are fired when a certain event is raised such as as insert, update or delete. The ManagingEnergy databases use triggers to maintain relationships with tables and also to ensure that records are inserted into the tables that must have a record when one exists in the parent table.
SQL Server 2000 allows you to define automatic update and delete relationships for only one foreign key per table. This causes a problem when there is more than one foreign key defined for a table and the items must maintain their relationship. If a table has more than one foreign key then typically triggers are used to maintain this relationship.