Question

having trouble coming up with search parameters for this issue, so I can’t find an answer on my own.

       Column X             |       Message (info 1)           | Message (info 2) (info 1)  | 

Above is the contents of one column I need to handle. The result of the query should be the part INSIDE the parentheses only. Problem is, there’s one program that saves two sets of information in parentheses, in which case the LATTER (info 1) is the one we want in the first column, in addition to which we must add a second column for info 2.

So I’m imagining I need to combine an if clause with a variable I can depend on to count how many left parentheses there are, for example. If left_parentheses = 2, Then …. Else If left_parentheses = 1, Then ….

But I don’t know how to do that in SQL, and I also don’t know how to separate between info 1 / 2 in the example.

The result from the example would look like this:

 Column 1 | Column 2  Info 1  |  Info 1  |  Info 2 

As usual, I’ll try to look for the answer while waiting for tips here. Thanks!

Answer 1

Here’s my go at it in SQL 2005 syntax using a Common Table Expression. I make no claims as to it’s correctness or it’s efficiency and I’ve made some assumptions about how you wanted it to work.

WITH BracketIndeces AS (   SELECT      ColumnX AS ColVal,     CHARINDEX('(', ColumnX) as first_open_bracket,     CHARINDEX('(', ColumnX, CHARINDEX('(', ColumnX)+1) as second_open_bracket,     CHARINDEX(')', ColumnX) as first_close_bracket,     CHARINDEX(')', ColumnX, CHARINDEX(')', ColumnX)+1) as second_close_bracket   FROM SomeTable ) SELECT   CASE     WHEN second_close_bracket = 0 THEN         SUBSTRING(ColVal, first_open_bracket+1, first_close_bracket - first_open_bracket-1)     ELSE         SUBSTRING(ColVal, second_open_bracket+1, second_close_bracket - second_open_bracket-1)         END AS Column1,   CASE     WHEN second_close_bracket = 0 THEN         NULL     ELSE         SUBSTRING(ColVal, first_open_bracket+1, first_close_bracket - first_open_bracket-1)   END AS Column2 FROM BracketIndeces WHERE first_open_bracket <> 0 AND first_close_bracket <> 0 AND first_open_bracket < first_close_bracket AND (   (second_open_bracket = 0 AND second_close_bracket = 0)    OR   (second_open_bracket < second_close_bracket      AND second_open_bracket > first_close_bracket   ) ) 

The where clause at the bottom is just to filter out any columns that either contain no brackets or contain brackets in a weird order and it uses NULL in Column2 when only one set of brackets are there.