Question

I am having some rows in table with some unusual character. When I use ascii() or unicode() for that character, it returns 63. But when I try this –

update MyTable
set MyColumn = replace(MyColumn,char(63),'') 

it does not replace. The unusual character still exists after the replace function. Char(63) incidentally looks like a question mark.

For example my string is ‘ddd#dd ddd’ where # it’s my unusual character and

select unicode('#')

return me 63.But this code

declare @str nvarchar(10) = 'ddd#dd ddd'
set @char = char(unicode('#'))
set @str = replace(@str,@char,'')

is working!

Any ideas how to resolve this?

Additional information:

select ascii('�') returns 63, and so does select ascii('?'). Finally select char(63) returns ? and not the diamond-question-mark.

When this character is pasted into Excel or a text editor, it looks like a space, but in an SQL Server Query window (and, apparently, here on StackOverflow as well), it looks like a diamond containing a question mark.

Answer 1

Not only does char(63) look like a ‘?’, it is actually a ‘?’.

(As a simple test ensure you have numlock on your keyboard on, hold down the alt key andtype ’63’ into the number pad – you can all sorts of fun this way, try alt-205, then alt-206 and alt-205 again: ═╬═)

Its possible that the ‘?’ you are seeing isn’t a char(63) however, and more indicitive of a character that SQL Server doesn’t know how to display.

What do you get when you run:

select ascii(substring('[yourstring]',[pos],1));
--or
select unicode(substring('[yourstring]',[pos],1));

Where [yourstring] is your string and [pos] is the position of your char in the string

EDIT

From your comment it seems like it is a question mark. Have you tried:

replace(MyColumn,'?','') 

EDIT2

Out of interest, what does the following do for you:

replace(replace(MyColumn,char(146),''),char(63),'')