![]() ![]() The triggers in SQLite will help us to maintain the data integrity on the database and these triggers will raise automatically to perform defined rules to prevent invalid transactions BEFORE or AFTER INSERT, UPDATE, or DELETE operations. The CASE expression is similar to the IF-THEN-ELSE statement in other programming languages. The SQLite CASE expression evaluates a list of conditions and returns an expression based on the result of the evaluation. ![]() Summary: in this tutorial, you will learn about the SQLite CASE expression to add the conditional logic to a query. If the UPDATE statement does not affect any row, the row level trigger is not executed at all. If the UPDATE statement affects 10 rows, the row level trigger would execute 10 times, each time per row. A row level trigger executes each time a row is affected by an UPDATE statement. There are two types of triggers: row and statement level triggers. Triggers are database operations that are automatically performed when a specified database event occurs. ![]() The CREATE TRIGGER statement is used to add triggers to the database schema. The statement CREATE TRIGGER creates a new trigger in SQLite. And here, we are using the CREATE TRIGGER Statement to create a trigger on the Employee table. In this example, we will show you how to create an After delete Triggers in SQL Server. After DELETE Triggers in SQL Server Example. NOTE: SQL After DELETE Triggers not Supported on Views. At this time, SQLite supports only FOR EACH ROW triggers, not FOR EACH STATEMENT triggers. SQLite trigger may be specified to fire whenever a DELETE, INSERT or UPDATE of a particular database table occurs or whenever an UPDATE occurs on one or more specified columns of a table. An SQLite trigger is a named database object that is executed automatically when an INSERT, UPDATE or DELETE statement is issued against the associated table. Summary: this tutorial discusses SQLite trigger, which is a database object fired automatically when the data in a table is changed. Note that triggers are automatically dropped when the associated table is dropped. Once removed, the trigger definition is no longer present in the sqlite_schema (or sqlite_temp_schema) table and is not fired by any subsequent INSERT, UPDATE or DELETE statements. The DROP TRIGGER statement removes a trigger created by the CREATE TRIGGER statement. ![]()
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