The Difference Between Truncate and Delete in SQL
When it comes to managing your data in SQL, there are two common commands that can come to mind: truncate and delete. While they may seem similar, they actually have distinct functionalities that could affect your database in different ways. In this article, we’ll dive into the differences between truncate and delete and when to use each command.
Truncate
Truncate is a command that removes all data from a table in a database. It essentially resets the table back to its initial state, without any data values. Unlike delete, truncate does not keep a record of the data that was removed. Because of this, it is a faster operation and consumes less overhead since it doesn’t involve logging each deletion.
Truncate can be useful when you need to completely reset a table due to a malfunction or testing purposes. However, one thing to keep in mind is that truncate cannot be undone. Once it is executed, the data is permanently deleted and cannot be recovered. For this reason, it’s important to analyze the situation and provide backup measures before executing the truncate command.
Delete
Delete is a command that removes one or more rows from a table in a database. Unlike truncate, delete is able to selectively remove specific data based on the filtering criteria. Delete is a slower operation and consumes more overhead since it has to log each deletion that takes place in the database.
Delete can be useful when you need to selectively remove specific data, such as removing inactive users from a user table. Delete also has a unique feature called the “rollback” option which allows you to recover data that was deleted using the delete command.
In summary, both truncate and delete are used to remove data from a table in a SQL database. While truncate removes all data from a table and is faster, it cannot be undone. Delete on the other hand removes specific data and is slower, but it has the capability to be undone using the rollback option. By understanding the differences between these commands, you can make informed decisions in managing your data in a SQL database.
Table difference between truncate and delete in sql
| Truncate | Delete |
|---|---|
| Removes all data from table but not table itself | Removes specific data or entire rows from table |
| Cannot be rolled back | Can be rolled back using transaction |
| Is faster as it doesn’t log individual row deletions | Is slower as it logs individual row deletions |
| Will not trigger any triggers on the table | Will trigger any triggers on the table |
| Resets identity column value to initial value | Doesn’t reset identity column value |