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SET ANSI_PADDING (Transact-SQL)

Controls the way the column stores values shorter than the defined size of the column, and the way the column stores values that have trailing blanks in char, varchar, binary, and varbinary data.

Important

In a future version of Microsoft SQL Server ANSI_PADDING will always be ON and any applications that explicitly set the option to OFF will produce an error. Avoid using this feature in new development work, and plan to modify applications that currently use this feature.

Topic link iconTransact-SQL Syntax Conventions

Syntax

SET ANSI_PADDING { ON | OFF }

Remarks

Columns defined with char, varchar, binary, and varbinary data types have a defined size.

This setting affects only the definition of new columns. After the column is created, SQL Server stores the values based on the setting when the column was created. Existing columns are not affected by a later change to this setting.

Note

We recommend that ANSI_PADDING always be set to ON.

The following table shows the effects of the SET ANSI_PADDING setting when values are inserted into columns with char, varchar, binary, and varbinary data types.

Setting

char(n) NOT NULL or binary(n) NOT NULL

char(n) NULL or binary(n) NULL

varchar(n) or varbinary(n)

ON

Pad original value (with trailing blanks for char columns and with trailing zeros for binary columns) to the length of the column.

Follows same rules as for char(n) or binary(n) NOT NULL when SET ANSI_PADDING is ON.

Trailing blanks in character values inserted into varchar columns are not trimmed. Trailing zeros in binary values inserted into varbinary columns are not trimmed. Values are not padded to the length of the column.

OFF

Pad original value (with trailing blanks for char columns and with trailing zeros for binary columns) to the length of the column.

Follows same rules as for varchar or varbinary when SET ANSI_PADDING is OFF.

Trailing blanks in character values inserted into a varchar column are trimmed. Trailing zeros in binary values inserted into a varbinary column are trimmed.

Note

When padded, char columns are padded with blanks, and binary columns are padded with zeros. When trimmed, char columns have the trailing blanks trimmed, and binary columns have the trailing zeros trimmed.

SET ANSI_PADDING must be ON when you are creating or changing indexes on computed columns or indexed views. For more information about required SET option settings with indexed views and indexes on computed columns, see "Considerations When You Use the SET Statements" in SET Statements (Transact-SQL).

The default for SET ANSI_PADDING is ON. The SQL Server Native Client ODBC driver and SQL Server Native Client OLE DB Provider for SQL Server automatically set ANSI_PADDING to ON when connecting. This can be configured in ODBC data sources, in ODBC connection attributes, or OLE DB connection properties set in the application before connecting. The default for SET ANSI_PADDING is OFF for connections from DB-Library applications.

The SET ANSI_PADDING setting does not affect the nchar, nvarchar, ntext, text, image, and large value. They always display the SET ANSI_PADDING ON behavior. This means trailing spaces and zeros are not trimmed.

When SET ANSI_DEFAULTS is ON, SET ANSI_PADDING is enabled.

The setting of SET ANSI_PADDING is set at execute or run time and not at parse time.

When ANSI_PADDING set to OFF, queries that involve MIN, MAX, or TOP on character columns might be slower than in SQL Server 2000.

Permissions

Requires membership in the public role.

Examples

The following example shows how the setting affects each of these data types.

PRINT 'Testing with ANSI_PADDING ON'
SET ANSI_PADDING ON;
GO

CREATE TABLE t1 (
   charcol CHAR(16) NULL, 
   varcharcol VARCHAR(16) NULL, 
   varbinarycol VARBINARY(8)
);
GO
INSERT INTO t1 VALUES ('No blanks', 'No blanks', 0x00ee);
INSERT INTO t1 VALUES ('Trailing blank ', 'Trailing blank ', 0x00ee00);

SELECT 'CHAR' = '>' + charcol + '<', 'VARCHAR'='>' + varcharcol + '<',
   varbinarycol
FROM t1;
GO

PRINT 'Testing with ANSI_PADDING OFF';
SET ANSI_PADDING OFF;
GO

CREATE TABLE t2 (
   charcol CHAR(16) NULL, 
   varcharcol VARCHAR(16) NULL, 
   varbinarycol VARBINARY(8)
);
GO
INSERT INTO t2 VALUES ('No blanks', 'No blanks', 0x00ee);
INSERT INTO t2 VALUES ('Trailing blank ', 'Trailing blank ', 0x00ee00);

SELECT 'CHAR' = '>' + charcol + '<', 'VARCHAR'='>' + varcharcol + '<',
   varbinarycol
FROM t2;
GO

DROP TABLE t1
DROP TABLE t2