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What is the difference between deleteband drop..

27th Jan 2017, 2:17 PM
yatharth jain
4 odpowiedzi
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using delete query we can delete whole database and drop we can delete table content
27th Jan 2017, 3:24 PM
bibhishan biradar
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Delete: The DELETE command is used to remove rows from a table. A WHERE clause can be used to only remove some rows. If no WHERE condition is specified, all rows will be removed. After performing a DELETE operation you need to COMMIT or ROLLBACK the transaction to make the change permanent or to undo it. Note that this operation will cause all DELETE triggers on the table to fire. Drop: The DROP command removes a table from the database. All the tables' rows, indexes and privileges will also be removed. No DML triggers will be fired. The operation cannot be rolled back.
3rd Feb 2017, 1:18 PM
Akwin Lopez
Akwin Lopez - avatar
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DELETE: 1. Removes Some or All rows from a table. 2. A WHERE clause can be used to remove some rows. If no WHERE condition is specified, all rows will be removed. 3. Causes all DELETE triggers on the table to fire. 4. It removes rows row-by-row one at a time and records an entry in the Transaction logs, thus is slower than TRUNCATE. 5. Every deleted row in locked, thus it requires more number of locks and database resources. 6. According to MS BOL, if a table is a Heap or no Clustered index is defined than the row-pages emptied are not de-allocated instantly and remain allocated in the heap. Thus, no other object can reuse this associated space. Thus to de-allocate the space a Clustered index is required or TABLOCK hint should be applied in the DELETE statement. 7. This is a DML command as it is just used to manipulate/modify the table data. It does not change any property of a table. DROP Command removes a table from the database. All the tables' rows, indexes and privileges will also be removed. No DML triggers will be fired. The operation cannot be rolled back.
9th Feb 2017, 9:42 AM
Akwin Lopez
Akwin Lopez - avatar