When it comes to deleting data from a table, there are two main commands that can be used: Delete and Truncate. Delete is a DML command, while Truncate is a DDL command. Both of these commands can be used to remove data from a table, but they have some key differences that should be taken into account. The Delete command allows you to delete specific data from the table, while maintaining the integrity of the table.
This means that any integrity compliance mechanisms will still be in place. However, the Delete command does log the changes that are made, so it can be part of a larger transaction and can be undone if necessary. The Truncate command, on the other hand, allows you to remove all data from the table without maintaining the integrity of the table. This means that any integrity compliance mechanisms will not be in place.
Additionally, Truncate does not record any information, but it does record the demapping of the data page of the table in which Truncate was activated. It's important to note that Truncate cannot be used in a table referenced by a FOREIGN KEY constraint, unless the table has a foreign key that references itself. Additionally, Truncate transactions can be undone in database engines such as SQL Server and PostgreSQL, but not in MySQL and Oracle. Therefore, Delete operations can be undone (undo), whereas Drop and Truncate operations cannot be undone.In short, when it comes to deleting data from a table, it's important to consider whether you need to maintain the integrity of the table or not.
If you do need to maintain the integrity of the table, then Delete is the best option. However, if you don't need to maintain the integrity of the table, then Truncate is a better option as it is faster and does not log any information.