sp_bindefault (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

Binds a default to a column or to an alias data type.

Important

This feature will be removed in a future version of SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. We recommend that you create default definitions by using the DEFAULT keyword of the ALTER TABLE or CREATE TABLE statements instead.

Transact-SQL syntax conventions

Syntax

sp_bindefault
    [ @defname = ] N'defname'
    , [ @objname = ] N'objname'
    [ , [ @futureonly = ] 'futureonly' ]
[ ; ]

Arguments

[ @defname = ] N'defname'

The name of the default created by CREATE DEFAULT. @defname is nvarchar(776), with no default.

[ @objname = ] N'objname'

The name of table and column, or the alias data type, to which the default is to be bound. @objname is nvarchar(776), with no default. @objname can't be defined with varchar(max), nvarchar(max), varbinary(max), xml, or CLR user-defined types.

If @objname is a one-part name, it resolves as an alias data type. If it's a two- or three-part name, it first resolves as a table and column; and if this resolution fails, it resolves as an alias data type. By default, existing columns of the alias data type inherit @defname, unless a default is bound directly to the column. A default can't be bound to a text, ntext, image, varchar(max), nvarchar(max), varbinary(max), xml, timestamp, or CLR user-defined type column, a column with the IDENTITY property, a computed column, or a column that already has a DEFAULT constraint.

@objname can contain brackets ([ and ]) as delimited identifiers. For more information, see Database identifiers.

[ @futureonly = ] 'futureonly'

Used only when binding a default to an alias data type. @futureonly is varchar(15), with a default of NULL. When this parameter is set to futureonly, existing columns of that data type can't inherit the new default. This parameter is never used when binding a default to a column. If @futureonly is NULL, the new default is bound to any columns of the alias data type that currently have no default or that are using the existing default of the alias data type.

Return code values

0 (success) or 1 (failure).

Remarks

You can use sp_bindefault to bind a new default to a column, although using the DEFAULT constraint is preferred, or to an alias data type without unbinding an existing default. The old default is overridden. You can't bind a default to a SQL Server system data type or a CLR user-defined type. If the default isn't compatible with the column to which you have bound it, the SQL Server Database Engine returns an error message when it tries to insert the default value, not when you bind it.

Existing columns of the alias data type inherit the new default, unless either a default is bound directly to them or futureonly is specified as futureonly. New columns of the alias data type always inherit the default.

When you bind a default to a column, related information is added to the sys.columns catalog view. When you bind a default to an alias data type, related information is added to the sys.types catalog view.

Permissions

User must own the table, or be a member of the sysadmin fixed server role, or the db_owner and db_ddladmin fixed database roles.

Examples

A. Bind a default to a column

A default named today is defined in the current database by using CREATE DEFAULT. The following example binds the default to the HireDate column of the Employee table. Whenever a row is added to the Employee table and data for the HireDate column isn't supplied, the column gets the value of the default today.

USE master;
GO

EXEC sp_bindefault 'today', 'HumanResources.Employee.HireDate';

B. Bind a default to an alias data type

A default named def_ssn and an alias data type named ssn already exists. The following example binds the default def_ssn to ssn. When a table is created, the default is inherited by all columns that are assigned the alias data type ssn. Existing columns of type ssn also inherit the default def_ssn, unless futureonly is specified for the @futureonly value, or the column has a default bound directly to it. Defaults bound to columns always take precedence over defaults bound to data types.

USE master;
GO

EXEC sp_bindefault 'def_ssn', 'ssn';

C. Use the futureonly option

The following example binds the default def_ssn to the alias data type ssn. Because futureonly is specified, no existing columns of type ssn are affected.

USE master;
GO

EXEC sp_bindefault 'def_ssn', 'ssn', 'futureonly';

D. Use delimited identifiers

The following example shows using delimited identifiers, [t.1], in @objname.

USE master;
GO

CREATE TABLE [t.1] (c1 int);
-- Notice the period as part of the table name.
EXEC sp_bindefault 'default1', '[t.1].c1';
-- The object contains two periods;
-- the first is part of the table name,
-- and the second distinguishes the table name from the column name.