Truncate and Delete in SQL are two commands which is used to remove or delete data from table. Though quite basic in nature both Sql commands can create lot of trouble until you are familiar with details before using it.
Truncate is a more powerful command that empties a table without logging each row. SQL Server prevents you from truncating a table with foreign keys referencing it, because of the need to check the foreign keys on each row. Truncate is normally ultra-fast, ideal for cleaning out data from a temporary table.
In SQL Server, it is possible to rollback a truncate operation if you are inside a transaction and the transaction has not been committed. From a SQL Server perspective, one key difference between DELETE FROM and TRUNCATE is this: "The DELETE statement removes rows one at a time and records an entry in the transaction log for each deleted row.
TRUNCATE reiniciará el contador para una tabla que contenga una columna IDENTITY. DELETE mantendrá el contador de la tabla para una columna IDENTITY. TRUNCATE es un comando DDL (lenguaje de definición de datos) mientras que DELETE es un DML (lenguaje de manipulación de datos). TRUNCATE no desencadena un TRIGGER, DELETE sí.
13 Truncating all of the tables will only work if you don't have any foreign key relationships between your tables, as SQL Server will not allow you to truncate a table with a foreign key. An alternative to this is to determine the tables with foreign keys and delete from these first, you can then truncate the tables without foreign keys ...
Why doesn't a TRUNCATE on mygroup work? Even though I have ON DELETE CASCADE SET I get: ERROR 1701 (42000): Cannot truncate a table referenced in a foreign key constraint (mytest.instance, CONSTR...
Cannot truncate table 'Test' because it is being referenced by a FOREIGN KEY constraint. Please suggest me how to delete or truncate table by dropping constraints temporarily.
No, you can only truncate a single table with TRUNCATE command. To truncate multiple tables you can use T-SQL and iterate through table names to truncate each at a time.
279 Because TRUNCATE TABLE is a DDL command, it cannot check to see whether the records in the table are being referenced by a record in the child table. This is why DELETE works and TRUNCATE TABLE doesn't: because the database is able to make sure that it isn't being referenced by another record.
