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By R.N. Sangwan-www.rnsangwan.com
To Learn or Teach visit www.theskillpedia.com
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• The Command used to create a database is :Create database
Syntaxcreate [inmemory] [temporary] database database_name
[use database_name as template]
[on {default | database_device} [= size]
[, database_device [= size]]...]
[log on database_device [= size]
[, database_device [= size]]...]
[with {dbid = number, default_location = "pathname", override}]
| [[,]durability = { no_recovery
| at_shutdown
| full} ]
}...
[for {load | proxy_update}]
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• Temporary - indicates that you are creating a temporary database.
• Inmemory - required for in-memory databases.
• database_name - is the name of the new database.
• On - indicates a location and size for the database.
• Default - indicates that create database can put the new database on any default database devices, as
shown in sysdevices.status.
To specify a size for the database without specifying a location, use:
on default = size
To change a database device’s status to “default,” use
sp_diskdefault.
• database_device- is the logical name of the device on which to locate the database. A database can
occupy different amounts of space on each of several database devices.
• Size - is the amount of space to allocate to the database extension.
• log on - specifies the logical name of the device for the database logs.
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• Adaptive Server can manage as many as 32,767 databases.
• The dbid should always be greater than zero and less than the
maximum dbid of 32,767.
• Adaptive Server can create only one database at a time.
• If two database creation requests collide, one user sees this message:
model database in use: cannot create new database
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• To get a report on a database, execute sp_helpdb.
• For a report on the space used in a database, use sp_spaceused
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• Creates a database named pubs10:• create database pubs10
• Creates a 4MB database named pubs11:• create database pubs11
• on default = 4
If you do not provide a unit specifier for size, the value provided for pubs is
presumed to be in megabytes.
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• Use sp_changedbowner to change the ownership of a database. System administrators
create the user databases, then give ownership to another user.
• Sybase suggests that you transfer ownership before the user has been added to the
database, and before the user has begun creating objects in the database.
• The new owner must already have a login name(User) on Adaptive Server, but cannot be a
user of the database, or have an alias in the database.
• You may have to use sp_dropuser or sp_dropalias before you can change a database’s
ownership, and you may have to drop objects before you can drop the user.
The syntax is:
sp_changedbowner loginame [, true ]
• This example makes “albert” the owner of the current database and drops aliases of users
who could act as the old “dbo:”
sp_changedbowner albert
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• Changes the owner of a user database.
• Syntaxsp_changedbowner loginame [, true ]
• Loginame is the login name of the new owner of the current database.
• True transfers aliases and their permissions to the new database owner. Values are “true” and
“TRUE”.
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• Makes the user “albert” the owner of the current database:sp_changedbowner albert
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• The new owner must not already be known as either a user or alias (that is, the new
owner must not already be listed in sysusers or sysalternates).
• Executing, with the single parameter loginame changes the database ownership
to loginame and drops aliases of users who could act as the old “dbo.”
• After executing, the new owner is known as the Database Owner inside the
database.
• It cannot transfer ownership of the system databases.
• The new owner must already have a login name in Adaptive Server, but
must not have a database user name or alias name in the database. To assign
database ownership to such a user, drop the user name or alias entry before
executing sp_changedbowner.
• A System Administrator must grant Permissions to the Database Owner, since the
user is no longer known inside the database under any other name.
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• First you have to extend the disk spaces allocated by the database server . This is done
with the disk init command. For example :
1>use master
2>go
3> disk init name='<ASE device name>', physname='<path to file in the directory>', size
='xxxxM', directio='true‘
• Next you have to alter the database so the database makes use of the new space
ALTER database PUBS10 on <ASE device name> = 'xxxxM’
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1> sp_helpdevice master
2> go• To expand the master database on the master device by 10MB, simply do the following:
alter database master on master = 10go
Extending database by 1280 pages (10.0 megabytes) on disk master
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• Use the drop database command to remove a database from SQL Server. When you run this
command, it:
• Frees the storage space allocated for the database
• Deletes references to it from the system tables in the master database
• Only the Database Owner can drop a database. You must be in the master database to drop a
database. You cannot drop a database that is open for reading or writing by a user.
Syntax
drop database database_name [, database_name]...
• You can drop more than one database in a single statement.
• For example:
You must drop all the databases drop database newpubs, newdb
• on a database device before you can drop the database device.
• The command to drop a device is sp_dropdevice.
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