DROP DATABASE (Transact-SQL)
Removes one or more databases or database snapshots from an instance of SQL Server.
To use DROP DATABASE, the database context of the connection cannot be the same as the database or database snapshot to be dropped.
The DROP DATABASE statement must run in autocommit mode and is not allowed in an explicit or implicit transaction. Autocommit mode is the default transaction management mode. For more information, see Autocommit Transactions.
Dropping a Database
System databases cannot be dropped.
Dropping a database deletes the database from an instance of SQL Server and deletes the physical disk files used by the database. If the database or any one of its files is offline when it is dropped, the disk files are not deleted. These files can be deleted manually by using Windows Explorer. To remove a database from the current server without deleting the files from the file system, use sp_detach_db.
You cannot drop a database currently being used. This means open for reading or writing by any user. To remove users from the database, use ALTER DATABASE to set the database to SINGLE_USER.
Any database snapshots on a database must be dropped before the database can be dropped.
If the database is involved in log shipping, remove log shipping before dropping the database. For more information, see Log Shipping Administration.
A database can be dropped regardless of its state: offline, read-only, suspect, and so on. To display the current state of a database, use the sys.databases catalog view.
A dropped database can be re-created only by restoring a backup. Database snapshots cannot be backed up and, therefore, cannot be restored.
When a database is dropped, the master database should be backed up.
Dropping a Database Snapshot
Dropping a database snapshot deletes the database snapshot from an instance of SQL Server and deletes the physical NTFS File System sparse files used by the snapshot. For information about using sparse files by database snapshots, see How Database Snapshots Work.
Dropping a database snapshot clears the plan cache for the instance of SQL Server. Clearing the plan cache causes a recompilation of all subsequent execution plans and can cause a sudden, temporary decrease in query performance. For each cleared cachestore in the plan cache, the SQL Server error log contains the following informational message: "SQL Server has encountered %d occurrence(s) of cachestore flush for the '%s' cachestore (part of plan cache) due to some database maintenance or reconfigure operations". This message is logged every five minutes as long as the cache is flushed within that time interval.
Dropping a Database Used in Replication
To drop a database published for transactional replication, or published or subscribed to merge replication, you must first remove replication from the database. For more information about how to remove replication from a database, see Removing Replication. If a database is damaged or replication cannot first be removed or both, in most cases you still can drop the database by using ALTER DATABASE to set the database offline and then dropping it.
A. Dropping a single database
The following example removes the Sales database.
DROP DATABASE Sales;
B. Dropping multiple databases
The following example removes each of the listed databases.
DROP DATABASE Sales, NewSales;
C. Dropping a database snapshot
The following example drops a database snapshot, named sales_snapshot0600, without affecting the source database.
DROP DATABASE sales_snapshot0600;