Difference Between Triggers and Cursors

A cursor can be created within a trigger by writing the declare statement inside the trigger. A trigger cannot be created within a cursor. ... A cursor is activated and thus created in response to any SQL statement. A trigger is executed in response to a DDL statement, DML statement or any database operation.

1. What is the difference between trigger and stored procedure?
2. What is difference between function and trigger?
3. What is difference between cursor and while loop?
4. Why do we use cursors?
5. What are the types of triggers?
6. What is trigger with example?
7. How do you explain triggers?
8. What trigger means?
9. What are the after triggers?
10. How do SQL cursors work?
11. Which is better cursor or temp table?
12. How do I create a cursor in SQL?

What is the difference between trigger and stored procedure?

Stored procedures are a pieces of the code in written in PL/SQL to do some specific task. On the other hand, trigger is a stored procedure that runs automatically when various events happen (eg update, insert, delete). ...

What is difference between function and trigger?

Function: We can call a function whenever required. Function can't be executed because a function is not in pre-compiled form. Trigger: Trigger can be executed automatically on specified action on a table like, update, delete, or update.

What is difference between cursor and while loop?

Cursors in sql server allow you to fetch a set of data, loop through each record, and modify the values as necessary; then, you can easily assign these values to variables and perform processing on these values. While loop also same as cursor to fetch set of data and process each row in sql server.

Why do we use cursors?

Use of Cursor

The major function of a cursor is to retrieve data, one row at a time, from a result set, unlike the SQL commands which operate on all the rows in the result set at one time. Cursors are used when the user needs to update records in a singleton fashion or in a row by row manner, in a database table.

What are the types of triggers?

Types of Triggers in Oracle

• DML Trigger: It fires when the DML event is specified (INSERT/UPDATE/DELETE)
• DDL Trigger: It fires when the DDL event is specified (CREATE/ALTER)
• DATABASE Trigger: It fires when the database event is specified (LOGON/LOGOFF/STARTUP/SHUTDOWN)

What is trigger with example?

Trigger: A trigger is a stored procedure in database which automatically invokes whenever a special event in the database occurs. For example, a trigger can be invoked when a row is inserted into a specified table or when certain table columns are being updated.

How do you explain triggers?

Triggers are anything that might cause a person to recall a traumatic experience they've had. For example, graphic images of violence might be a trigger for some people. Less obvious things, including songs, odors, or even colors, can also be triggers, depending on someone's experience.

What trigger means?

Trigger: Something that either sets off a disease in people who are genetically predisposed to developing the disease, or that causes a certain symptom to occur in a person who has a disease. For example, sunlight can trigger rashes in people with lupus. A predisposing event.

What are the after triggers?

What are the after triggers? Explanation: AFTER TRIGGERS can be classified further into three types as: AFTER INSERT Trigger, AFTER UPDATE Trigger, AFTER DELETE Trigger. Explanation: Example : declare @empid int; where empid is the variable.

How do SQL cursors work?

SQL Cursor Life Cycle

A cursor is declared by defining the SQL statement. A cursor is opened for storing data retrieved from the result set. When a cursor is opened, rows can be fetched from the cursor one by one or in a block to do data manipulation. The cursor should be closed explicitly after data manipulation.

Which is better cursor or temp table?

Neither is better. If your requirement is simply to compare data between two tables then you can do it as a set based operation without using a Cursor. I would advise the use of Cursors only if don't have any other Set Based option to do the work.

How do I create a cursor in SQL?

Explanation of Cursor Syntax in SQL Server

1. DECLARE statements - Declare variables used in the code block.
2. SET\SELECT statements - Initialize the variables to a specific value.
3. DECLARE CURSOR statement - Populate the cursor with values that will be evaluated. ...
4. OPEN statement - Open the cursor to begin data processing.