Removing an entire line when only the beginning string is known - sql

Question

I am trying to remove any line that has a particular substring Signed By: in it.
So the original string would look like:
information on line 1
information on line 2
Signed By: John Smith
information on an additional line
Signed By: Jane Doe
And after the removal of the lines
information on line 1
information on line 2
information on an additional line
The issue I am running into is while I can easily replace Signed By: I need to remove the name after it as well which can have a very different number of characters.
EDIT
To make the issue clearer, all of this is contained in a single field within the database. So I would get the entire original string if I was to say
SELECT TOP 1 NoteValue
FROM Notes

Answer 1

You can use a split function to split the string into rows based on char(13) or char(10). Then, stuff it back together with for xml.
ONLINE DEMO
declare #table table (strr varchar(4000))
insert into #table
values
('information on line 1
Signed By: John Smith
information on line 2
Signed By: John Smith
information on an additional line
Signed By: Jane Doe')
select
stuff(( SELECT ' ' + x.Item
from #table
cross apply DelimitedSplit8K(strr,char(13)) x
where Item not like '%Signed By:%'
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, '')
RETURNS
information on line 1
information on line 2
information on an additional line
HERE IS THE SPLITTER I USE
USE [Test01]
GO
/****** Object: UserDefinedFunction [dbo].[DelimitedSplit8K] Script Date: 09/15/2017 9:59:16 AM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[DelimitedSplit8K] (#pString VARCHAR(8000), #pDelimiter CHAR(1))
--WARNING!!! DO NOT USE MAX DATA-TYPES HERE! IT WILL KILL PERFORMANCE!
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
/* "Inline" CTE Driven "Tally Table" produces values from 1 up to 10,000...
enough to cover VARCHAR(8000)*/
WITH E1(N) AS (
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
), --10E+1 or 10 rows
E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
-- for both a performance gain and prevention of accidental "overruns"
SELECT TOP (ISNULL(DATALENGTH(#pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
SELECT 1 UNION ALL
SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(#pString,t.N,1) = #pDelimiter
),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
SELECT s.N1,
ISNULL(NULLIF(CHARINDEX(#pDelimiter,#pString,s.N1),0)-s.N1,8000)
FROM cteStart s
)
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
Item = SUBSTRING(#pString, l.N1, l.L1)
FROM cteLen l
;
GO

Answer 2

You could try
SELECT TOP 1
CASE WHEN PATINDEX(NoteValue,'%Signed by%')>0
THEN LEFT(NoteValue, PATINDEX(NoteValue,'%Signed by%')-1)
ELSE NoteValue
END FROM Notes

Answer 3

Another solution using TSQL
DECLARE #document varchar(max);
SET #document = 'information on line 1
information on line 2
Signed By: John Smith
information on an additional line
Signed By: Jane Doe';
DECLARE #index int =0;
DECLARE #newLineindex int =0;
DECLARE #ReplaceText varchar(100) = 'Signed'
SELECT CHARINDEX(#ReplaceText, #document, #index)
WHILE ((SELECT CHARINDEX(#ReplaceText, #document, #index)) > 0)
BEGIN
SELECT #index = CHARINDEX(#ReplaceText, #document, #index);
SELECT #newLineindex = CHARINDEX(CHAR(13), #document, #index);
IF(#newLineindex >#index)
BEGIN
SET #document = REPLACE(#document, SUBSTRING ( #document ,#index , (#newLineindex - #index)), '')
END
ELSE
BEGIN
SET #document = REPLACE(#document, SUBSTRING ( #document ,#index , ((len(#document) - #index) +1)), '')
END
SET #index =0
END
SELECT #document