Using PATINDEX to find varying length patterns in T-SQL

Question

I\'m looking to pull floats out of some varchars, using PATINDEX() to spot them. I know in each varchar string, I\'m only interested in the first float that exists, but they

Answer 1

Given that the pattern is going to be varied in length, you're not going to have a rough time getting this to work with PATINDEX. There is another post that I wrote, which I've modified to accomplish what you're trying to do here. Will this work for you?

CREATE TABLE #nums (n INT)
DECLARE @i INT 
SET @i = 1
WHILE @i < 8000 
BEGIN
    INSERT #nums VALUES(@i)
    SET @i = @i + 1
END

CREATE TABLE #tmp (
  id INT IDENTITY(1,1) not null,
  words VARCHAR(MAX) null
)

INSERT INTO #tmp
VALUES('I''m looking for a number, regardless of length, even 23.258 long'),('Maybe even pi which roughly 3.14159265358,'),('or possibly something else that isn''t a number')

UPDATE #tmp SET words = REPLACE(words, ',',' ')

;WITH CTE AS (SELECT ROW_NUMBER() OVER (ORDER BY ID) AS rownum, ID, NULLIF(SUBSTRING(' ' + words + ' ' , n , CHARINDEX(' ' , ' ' + words + ' ' , n) - n) , '') AS word
    FROM #nums, #tmp
    WHERE ID <= LEN(' ' + words + ' ') AND SUBSTRING(' ' + words + ' ' , n - 1, 1) = ' ' 
    AND CHARINDEX(' ' , ' ' + words + ' ' , n) - n > 0),
    ids AS (SELECT ID, MIN(rownum) AS rownum FROM CTE WHERE ISNUMERIC(word) = 1 GROUP BY id)
SELECT CTE.rownum, cte.id, cte.word
FROM CTE, ids WHERE cte.id = ids.id AND cte.rownum = ids.rownum

The explanation and origin of the code is covered in more detail in the origional post