I've been looking at this code, reproduced below, that looks for non-ASCII characters...
select line,
patindex('%[^ !-~]%' COLLATE Latin1_General_BIN, Line) as [Position],
substring(Line, patindex('%[^ !-~]%' COLLATE Latin1_General_BIN, Line), 1) as [InvalidCharacter],
ascii(substring(line, patindex('%[^ !-~]%' COLLATE Latin1_General_BIN, Line), 1)) as [ASCIICode]
from staging.APARMRE1
where patindex('%[^ !-~]%' COLLATE Latin1_General_BIN, Line) > 0
and it just strikes me that I'd want to declare a variable for '%[^ !-~]%' COLLATE Latin1_General_BIN
instead of writing it out every time, but
declare @regex varchar(20) = '%[^ !-~]%' COLLATE Latin1_General_BIN;
select line,
patindex(@regex, Line) as [Position],
substring(Line, patindex(@regex, Line), 1) as [InvalidCharacter],
ascii(substring(line, patindex(@regex, Line), 1)) as [ASCIICode]
from staging.APARMRE1
where patindex(@regex, Line) > 0
just doesn't do the same thing. Am I just missing some syntax? Is it impossible?
It is normal. When you create a variable it takes default collation for database.
DECLARE @regex varchar(20) = '%[^ !-~]%' COLLATE Latin1_General_BIN;
Your string with COLLATE Latin1_General_BIN
is implicitly casted to string with your database default collation.
Case-Insensitive
. I use your syntax to create case-sensitive one and check metadata of it:
DECLARE @v1 varchar(100) = 'ABC' COLLATE Latin1_General_CS_AS;
SELECT name, collation_name
FROM sys.dm_exec_describe_first_result_set(
N'SELECT @v1 AS [@v1]', N'@v1 varchar(100)', 0);
Output:
╔══════╦══════════════════════════════╗
║ name ║ collation_name ║
╠══════╬══════════════════════════════╣
║ @v1 ║ SQL_Latin1_General_CP1_CI_AS ║
╚══════╩══════════════════════════════╝
Variables(excluding columns in table variables) do not allow to define collation so there is no syntax like:
DECLARE @v1 varchar(100) COLLATE Latin1_General_CS_AS = 'ABC' ;
-- Incorrect syntax near the keyword 'COLLATE'.