What is the easiest way using T-SQL / MS-SQL to append a string to existing table cells?

Question

I have a table with a 'filename' column. I recently performed an insert into this column but in my haste forgot to append the file extension to all the filenames entered. Fortunately they are all '.jpg' images.

How can I easily update the 'filename' column of these inserted fields (assuming I can select the recent rows based on known id values) to include the '.jpg' extension?

Answer 1

MattMitchell's answer is correct if the column is a CHAR(20), but is not true if it was a VARCHAR(20) and the spaces hadn't been explicitly entered.

If you do try it on a CHAR field without the RTRIM function you will get a "String or binary data would be truncated" error.

Answer 2

The solution is:

UPDATE tablename SET [filename] = RTRIM([filename]) + '.jpg' WHERE id > 50

RTRIM is required because otherwise the [filename] column in its entirety will be selected for the string concatenation i.e. if it is a varchar(20) column and filename is only 10 letters long then it will still select those 10 letters and then 10 spaces. This will in turn result in an error as you try to fit 20 + 3 characters into a 20 character long field.

Answer 3

Nice easy one I think.

update MyTable
set filename = filename + '.jpg'
where ...

Edit: Ooh +1 to @MattMitchell's answer for the rtrim suggestion.