SQL to filter by multiple criteria including containment in string list

Question

so i have a table lets say call it "tbl.items" and there is a column "title" in "tbl.items" i want to loop through each row and for each "title" in "tbl.items" i want to do following: the column has the datatype nvarchar(max) and contains a string...

1. filter the string to remove words like in,out, where etc (stopwords)
2. compare the rest of the string to a predefined list and if there is a match perform some action which involves inserting data in other tables as well..

the problem is im ignotent when it comes to writing T-sql scripts, plz help and guide me how can i achieve this? whether it can be achieved by writing a sql script?? or i have to develope a console application in c# or anyother language??

im using mssql server 2008

thanks in advance

Answer 1

You want a few things. First, look up SQL Server's syntax for functions, and write something like this:

-- Warning! Code written off the top of my head,
-- don't expect this to work w/copy-n-paste
create function removeStrings(@input nvarchar(4000))
as begin
    -- We're being kind of simple-minded and using strings
    -- instead of regular expressions, so we are assuming a
    -- a space before and after each word.  This makes this work better:
    @input = ' ' + @input

    -- Big list of replaces
    @input = replace(' in ','',@input)
    @input = replace(' out ','',@input)
    --- more replaces...
end

Then you need your list of matches in a table, call this "predefined" with a column "matchString".

Then you can retrieve the matching rows with:

select p.matchString
  from items i
  join predefined p 
    on removeStrings(i.title) = p.matchString

Once you have those individual pieces working, I suggest a new question on what particular process you may be doing with them.

Warning: Not knowing how many rows you have or how often you have to do this (every time a user saves something? Once/day?), this will not exactly be zippy, if you know what I mean. So once you have these building blocks in hand, there may also be a follow-up question for how and when to do it.