Which of the following statements about triggers is correct
The correct is option 4. Trigger is a statement that is executed automatically by the system as a side effect of modification to the database. Trigger has three parts: Trigger statement or event is the SQL statement that causes a trigger to be fired.
Which of the following is not correct for trigger
|Q.||Which of the following is not true in case of triggers?|
|A.||Triggers accept parameters.|
|B.||Triggers are executed implicitly|
|C.||Execution of triggers is transparent to the users.|
|D.||A trigger can invoke another trigger.|
Why trigger is used in database
A database trigger is procedural code that is automatically executed in response to certain events on a particular table or view in a database. The trigger is mostly used for maintaining the integrity of the information on the database.
What are benefits of trigger in SQL
Benefits of Triggers
- Generating some derived column values automatically.
- Enforcing referential integrity.
- Event logging and storing information on table access.
- Synchronous replication of tables.
- Imposing security authorizations.
- Preventing invalid transactions.
What are the after triggers
An after trigger runs after the corresponding insert, update, or delete changes are applied to the table. The WHEN condition can be used in an SQL trigger to specify a condition. If the condition evaluates to true, the SQL statements in the SQL trigger routine body are run.
Which of the following keywords can you use in a trigger to work with the values in a row
When you use a BEFORE trigger to work with an UPDATE statement, you can use the BLANK keyword and a column name to refer to a value in the row before it is updated.
Which of the following triggers can be defined only on views and not on table
BEFORE and AFTER triggers fired by DML statements can be defined only on tables, not on views. However, triggers on the base tables of a view are fired if an INSERT , UPDATE , or DELETE statement is issued against the view.
What is trigger in PL SQL
A PL/SQL trigger is a named database object that encapsulates and defines a set of actions that are to be performed in response to an insert, update, or delete operation against a table. Triggers are created using the PL/SQL CREATE TRIGGER statement.
Which of the following clauses must you include on the Create trigger statement to create a row level trigger
To create a new row-level trigger, you use the CREATE TRIGGER statement with the FOR EACH ROW clause.
Which of the following statement is true concerning routines and triggers both consist of procedural code both have to be called to operate both run automatically Na skip
Answer» a. Both consist of procedural code.
Which statement is true about indexes
5. What is true about indexes? Explanation: Indexes tend to improve the performance.
Which of the following is true about the SQL AS clause
The AS clause in SQL is used to change the column name in the output or assign a name to a derived column.
Which of the following is not a valid SQL type
2) Which of the following is not a valid SQL type? Explanation: DECIMAL is not a valid SQL type because it is nothing but numeric only in SQL. NUMERIC has fixed precision, and scale numbers range from -10^38+1 to 10^38-1.
Which of the following are TCL commands
List of TCL commands:
- COMMIT: Commits a Transaction.
- ROLLBACK: Rollbacks a transaction in case of any error occurs.
- SAVEPOINT:Sets a savepoint within a transaction.
- SET TRANSACTION: Specify characteristics for the transaction.
Which SQL statement is used to insert a new data in a database
The INSERT INTO statement is used to insert new records in a table.
Which of the following is valid statement for triggers
Explanation: Valid trigger actions are INSERT, UPDATE and DELETE, or a combination of several, separated by commas. 10.
In which of the following events are triggers used
Triggers are written to be executed in response to any of the following events. A database manipulation (DML) statement (DELETE, INSERT, or UPDATE). A database definition (DDL) statement (CREATE, ALTER, or DROP). A database operation (SERVERERROR, LOGON, LOGOFF, STARTUP, or SHUTDOWN).
What is the purpose of trigger Mcq
what is the purpose of triggers ? All of the mentioned above ( the purpose of triggers are Enforcing referential integrity, Synchronous replication of tables and Preventing invalid transactions.