What is the Difference Between Triggers and Cursors?
🆚 Go to Comparative Table 🆚The main difference between triggers and cursors lies in their purpose and how they are used in a database system.
Triggers:
- Triggers are procedures (code segments) that are executed automatically when specific events occur in a table or view of a database.
- They are primarily used to maintain the integrity of the database and automate actions based on data changes.
- Triggers are executed in response to DDL statements, DML statements, or any database operation.
- They are hard to view, which can make debugging challenging.
Cursors:
- Cursors are control structures used in databases to go through the database records.
- They facilitate row-by-row processing and validation on each row.
- Cursors are activated and created in response to any SQL statement.
- They are faster than while loops and provide better concurrency control.
In summary, triggers are used to automate actions based on data changes and are executed in response to specific events, while cursors are used for row-by-row processing and validation of data in a database.
Comparative Table: Triggers vs Cursors
Here is a table comparing the differences between triggers and cursors:
| Feature | Triggers | Cursors |
|---|---|---|
| Purpose | Automate actions based on data changes and maintain database integrity | Retrieve and process data, primarily used to reduce network traffic and control record access |
| Execution | Automatically executed by the database in response to specified events (DDL, DML, or database operations) | Explicitly opened and closed by the programmer, activated and created in response to any SQL statement |
| Declaration | Cannot be created within a cursor | Can be created within a trigger by writing the declare statement inside the trigger |
| Scope | Previously stored program | Retrieves rows from the result set one at a time (row by row) |
| Activation | Executed in response to a DDL, DML, or database operation | Activated and created in response to any SQL statement |
| Disadvantages | Can be hard to view, making them difficult to manage | Uses more resources each time, which can result in network traffic issues |
In summary, triggers are used to automate actions based on data changes and maintain database integrity, while cursors are used to retrieve and process data, primarily to reduce network traffic and control record access. Triggers are automatically executed by the database in response to specified events, whereas cursors are explicitly opened and closed by the programmer and activated in response to any SQL statement.
- Triggers vs Stored Procedures
- Explicit Cursor vs Implicit Cursor
- Interrupt vs Trap
- Cue vs Queue
- Drop vs Truncate
- Keyboard vs Mouse
- Pointer vs Reference
- Delete vs Truncate
- Criteria vs Criterion
- Goals vs Targets
- Trap vs Skeet
- Insert vs Update vs Alter
- Pointer vs Array
- Fetch vs Push
- Interrupt vs Exception
- Piston vs Plunger
- DDL vs DML
- SQL vs MySQL
- SQL vs T-SQL