DROP DATABASE (Transact-SQL)
Removes one or more user databases or database snapshots from an instance of SQL Server or user databases from the Windows Azure SQL Database server.
Applies to: SQL Server (SQL Server 2008 through current version), Windows Azure SQL Database (Initial release through current release). |
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Transact-SQL Syntax Conventions
Składnia
-- SQL Server Syntax
DROP DATABASE { database_name | database_snapshot_name } [ ,...n ] [;]
-- Windows Azure SQL Database Syntax
DROP DATABASE database_name [;]
-- Core Syntax (common to SQL Server and SQL Database)
DROP DATABASE database_name [;]
Arguments
database_name
Specifies the name of the database to be removed. To display a list of databases, use the sys.databases catalog view.database_snapshot_name
Specifies the name of a database snapshot to be removed.Applies to: SQL Server only.
General Remarks
Core
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.
SQL Server
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.
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 Database Snapshots (SQL Server). 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.
Windows Azure SQL Database
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.
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.
Interoperability
SQL Server
To drop a database published for transactional replication, or published or subscribed to merge replication, you must first remove replication from the database. 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.
If the database is involved in log shipping, remove log shipping before dropping the database. For more information, see About Log Shipping (SQL Server).
Windows Azure SQL Database
None
Limitations and Restrictions
Core
System databases cannot 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.
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.
SQL Server
Any database snapshots on a database must be dropped before the database can be dropped.
Windows Azure SQL Database
You must be connected to the master database to drop a database.
The DROP DATABASE statement must be the only statement in a SQL batch and you can drop only one database at a time.
Permissions
SQL Server
Requires the CONTROL permission on the database, or ALTER ANY DATABASE permission, or membership in the db_owner fixed database role.
Windows Azure SQL Database
Only the server-level principal login (created by the provisioning process) or members of the dbmanager database role can drop a database.
Examples
A. Dropping a single database
The following example removes the Sales database.
Applies to: SQL Server and Windows Azure SQL Database |
DROP DATABASE Sales;
B. Dropping multiple databases
The following example removes each of the listed databases.
Applies to: SQL Server |
DROP DATABASE Sales, NewSales;
C. Dropping a database snapshot
The following example removes a database snapshot, named sales_snapshot0600, without affecting the source database.
Applies to: SQL Server |
DROP DATABASE sales_snapshot0600;