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What would happen when the trigger is fired?
When a trigger is fired, the tables referenced in the trigger action might be currently undergoing changes by SQL statements contained in other users’ transactions. In all cases, the SQL statements executed within triggers follow the common rules used for standalone SQL statements.
Who will fire a trigger?
Triggers are implicitly fired by Oracle when a triggering event occurs, no matter which user is connected or which application is being used. Figure 22-1 shows a database application with some SQL statements that implicitly fire several triggers stored in the database.
What is trigger execution?
Triggers are stored programs that are automatically executed or fired when a specified event occurs. It is a database object that is bound to a table and is executed automatically. Triggers provide data integrity and are used to access and check data before and after modification using DDL or DML queries.
Can a trigger execute a stored procedure?
A: Yes, we can call stored procedure inside the trigger. For example: Create PROCEDURE [dbo].
What is the order of execution?
Order execution is the process of accepting and completing a buy or sell order in the market on behalf of a client. Order execution may be carried out manually or electronically, subject to the limits or conditions placed on the order by the account holder.
Can rollback or COMMIT issued inside a trigger code?
3 Answers. Not only do triggers not need a COMMIT you can’t put one in: a trigger won’t compile if the body’s code includes a COMMIT (or a rollback). This is because triggers fire during a transaction. When the trigger fires the current transaction is still not complete.
Can we COMMIT after rollback?
1 Answer. No, you can’t undo, rollback or reverse a commit.
When to write triggers that fire in Oracle?
You can write triggers that fire whenever one of the following operations occurs: DML statements ( INSERT, UPDATE, DELETE) on a particular table or view, issued by any user DDL statements ( CREATE or ALTER primarily) issued either by a particular schema/user or by any schema/user in the database
Which is an example of a triggering event in SQL?
A triggering event or statement is the SQL statement, database event, or user event that causes a trigger to fire. A triggering event can be one or more of the following: An INSERT, UPDATE, or DELETE statement on a specific table (or view, in some cases) A CREATE, ALTER, or DROP statement on any schema object.
How does trigger work when INSERT statement is fired?
A trigger fired by an INSERT statement will always report that all columns were updated – even if they weren’t. This will update the 1 row in the target table.
How does create trigger for update work in SQL Server?
For example, if CREATE TRIGGER FOR UPDATE is run for a table that already has an UPDATE trigger, an additional update trigger is created. In earlier versions of SQL Server, only one trigger for each INSERT, UPDATE, or DELETE data modification event is allowed for each table.