How can I extract all literal strings from text in SQL server? - sql-server

Question

I need to extract all the literal strings from my SQL server stored procedures and put them in a table. I tried to use Jeff Moden's and other string splitters, but all the code in between the quoted strings gets in the way and is hard to identify as not useful. The most simple example of what I am trying to accomplish:
input = "SELECT * FROM table WHERE column IN ('cool','super', 'awesome')
output table:
cool
super
awesome
Here is an example using the sp_help stored procedure.
USE master
SELECT * FROM sys.system_sql_modules where OBJECT_NAME(object_id) = 'sp_help'
I want the output to be ONLY the single quoted items contained in sp_help - here is the snippet of sp_help.
create procedure sys.sp_help
#objname nvarchar(776) = NULL -- object name we're after
as
-- PRELIMINARY
set nocount on
declare #dbname sysname
,#no varchar(35), #yes varchar(35), #none varchar(35)
select #no = 'no', #yes = 'yes', #none = 'none'
-- If no #objname given, give a little info about all objects.
if #objname is null
begin
-- DISPLAY ALL SYSOBJECTS --
select
'Name' = o.name,
'Owner' = user_name(ObjectProperty( object_id, 'ownerid')),
'Object_type' = substring(v.name,5,31)
from sys.all_objects o, master.dbo.spt_values v
where o.type = substring(v.name,1,2) collate database_default and v.type = 'O9T'
order by [Owner] asc, Object_type desc, Name asc
The output would be to a table:
- no
- yes
- none
- Name
- Owner
- ownerid
- Object_type
- O9T
Does anyone have anything like this already or can adapt one of the common string splitters to ignore the stuff in between opposing quoted items?

Answer 1

Here's a small test I made. The find_next function is a replacement for charindex. The difference is that when it's looking the end of the string, it will skip '' to prevent that from ending the string. If that happens it will call itself recursively:
CREATE FUNCTION find_next (#str nvarchar(MAX), #start int, #mode int)
returns bigint
as
begin
declare #pos int
set #pos = charindex('''', #str, #start)
if (#pos = 0) return 0
if (#mode = 1) return #pos
if (substring(#str, #pos+1,1)='''') return dbo.find_next(#str, #start+2, #mode)
return #pos
end
And a recursive CTE based function to find the strings:
CREATE FUNCTION find_strs (#str nvarchar(MAX))
RETURNS TABLE AS
RETURN
WITH CTE AS (
select
convert(bigint, 1) as start,
charindex('''', #str) as stop,
0 as type
UNION ALL
select
stop + 1,
dbo.find_next(#str, stop + 1, type),
(type + 1) % 2
FROM CTE
WHERE stop > 0
)
SELECT substring(#str, start, CASE WHEN stop > 0 THEN stop - start ELSE 0 END) as Str
FROM CTE
WHERE stop > 0 and type = 1
Simple example in SQL Fiddle