Collation Ansi Padding And Trailing Blanks

Hi,

This might sound obvious, or a newbie question, but how are trailing blanks treated by SQL2005 on varchar columns?

I have a column where two rows only differ by a trailing blank. If write a select and a where clause on the column, anly trailing blanks seem to be trimmed. I tried the ansi padding setting but it doesn't change anything. Is it a question of collation? I have default collation on the server set to SQL_Latin1_General_CP1_CI_AS...

The problem also seems to arise when I try to create a unique index on the column, where both values are considered equivalent...

I give here a sample based on the BOL for set ansi_padding. I was expecting each of the select statements below to retrun only one row...

Cany somebody please explain why they all return two rows?

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);

INSERT INTO t1 VALUES ('Trailing blank ', 'Trailing blank', 0x00ee00);

SELECT 'CHAR' = '>' + charcol + '<', 'VARCHAR'='>' + varcharcol + '<',

varbinarycol

FROM t1

where varcharcol='Trailing blank';

GO

SELECT 'CHAR' = '>' + charcol + '<', 'VARCHAR'='>' + varcharcol + '<',

varbinarycol

FROM t1

where varcharcol='Trailing blank ';

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);

INSERT INTO t2 VALUES ('Trailing blank ', 'Trailing blank', 0x00ee00);

SELECT 'CHAR' = '>' + charcol + '<', 'VARCHAR'='>' + varcharcol + '<',

varbinarycol

FROM t2

where varcharcol='Trailing blank';

GO

SELECT 'CHAR' = '>' + charcol + '<', 'VARCHAR'='>' + varcharcol + '<',

varbinarycol

FROM t2

where varcharcol='Trailing blank ';

GO

DROP TABLE t1

DROP TABLE t2