Remove everything after a specific special character in SQL Server - sql

Question

This Question is pretty much answered in this forum but for my situation which is exactly the same the answers I find here are not working.
I'm trying to remove all the characters after the pipe " | " in sql server. Any suggestions why it's not working?
query that i'm using:
SELECT left(name, charindex('|',name) -1) from table1
Error:
Invalid length parameter passed to the LEFT or SUBSTRING function.
table1:
name
----
jack| rose|
wil |jo|rdy
karl||jay
jo smith
jjill
raj |kumar
Desired output:
name
----
jack
wil
karl
jo smith
jjill
raj

Answer 1

try:
select LEFT(name,CHARINDEX('|',name + '|')-1)
from table1

Answer 2

Think you're almost there - you just need to filter to ensure you aren't passing a negative number to the LEFT
e.g.,
SELECT left(name, charindex('|',name) -1) from table1
WHERE name LIKE '%|%'
Remember charindex is 0 if it doesn't exist in string, then you subtract 1. This means you're trying to do a LEFT(name, -1) which is invalid.
To get your full output (with all rows, regardless of the | symbol) you can use it in a CASE instead.
SELECT CASE
WHEN [name] LIKE '%|%' THEN left(name, charindex('|',name) -1)
ELSE [name] END AS [name]
from table1
Edit: Here's a db<>fiddle with results.

Answer 3

You can try the below -
SELECT left(name, case when charindex('|',name)=0 then len(name)
else charindex('|',name)-1 end),charindex('|',name)
from tablename

Answer 4

based on your query, its expecting values to have | always. So this will error on name = jo smith'. Use select case to solve this.
declare #str varchar(200)
set #str = 'jo smith'
select case when charindex('|',#str) > 0 then left(#str, charindex('|',#str) -1) else #str end

Answer 5

Instead of using LEFT, use a combination of STUFF and ISNULL.
While LEFT will raise the "Invalid length parameter passed to the left function." error if it gets a negative length parameter,
STUFF will simply return null if it's starting position argument is less than less than 1.
This means that if the original value doesn't contain | and charindex return 0, stuff will simply return null, and you can use ISNULL to return the original value in this case.
First, create and populate sample table (Please save us this step in your future questions):
DECLARE #T TABLE (
[name] varchar(20)
);
INSERT INTO #T ([name]) VALUES
('jack| rose|'),
('wil |jo|rdy'),
('karl||jay'),
('jo smith'),
('jjill'),
('raj |kumar');
The query:
SELECT [name],
ISNULL(STUFF([name], CHARINDEX('|', [name]), LEN([name]), ''), [name]) As Replaced
FROM #T
Results:
name Replaced
jack| rose| jack
wil |jo|rdy wil
karl||jay karl
jo smith jo smith
jjill jjill
raj |kumar raj