Subtract two CHARINDEX values

Question

Update - let's look at the second field and I get results just fine... I still get the error of the first.. I need to figure out the first.. I think what I need to is to remove the first..

This works.. Second length

SELECT  SUBSTRING(AFIELD,
CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1),
CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1)+1) - CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1)) as [second_length]
FROM SOMETABLE with (nolock)

Third length which also works..

SELECT SUBSTRING(AFIELD,
CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1),
CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1)+1)-CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1)) as [THIRD_length]
FROM SOMETABLE with (nolock)

This is still not working.. Hmmm..

SELECT SUBSTRING(AFIELD,
CHARINDEX(CHAR(10), AFIELD),
CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1)-CHARINDEX(CHAR(10), AFIELD)) as [FIRST_length]
FROM SOMETABLE with (nolock)

Old info.. This works fine..

SELECT CHARINDEX(CHAR(10), AFIELD)[first]
,CHARINDEX(CHAR(10), AFIELD,CHARINDEX(CHAR(10), AFIELD)+1)[second]
FROM SOMETABLE

But when I try to subtract the two, the results are empty..

I have followed the information posted here and at - http://phelabaum.com/archive/tag/charindex/

SELECT  SUBSTRING(AFIELD,
CHARINDEX(CHAR(10),AFIELD)+1,
CHARINDEX(CHAR(10),AFIELD,CHARINDEX(CHAR(10),AFIELD)+1) - CHARINDEX(CHAR(10),AFIELD)) as [first_length]
FROM SOMETABLE

When I run this, I get: the message:

Msg 537, Level 16, State 3, Line 1 Invalid length parameter passed to the LEFT or SUBSTRING function.

The field is CHAR(10) or Line Feed delimited.

Answer 1

It works fine if text you're testing indeed has 2 CHAR(10) in it with some text in between. If at least one is missing - you will get that error.

Note that CHARINDEX by itself will not return any errors if char is not found - it will simple return 0, this is why your first query runs.