How to use a TRIM function in SQL Server - sql

Question

I cannot get this TRIM code to work
SELECT
dbo.COL_V_Cost_GEMS_Detail.TNG_SYS_NR AS [EHP Code],
dbo.COL_TBL_VCOURSE.TNG_NA AS [Course Title],
LTRIM(RTRIM(FCT_TYP_CD)& ') AND (' & LTRIM(RTRIM(DEP_TYP_ID) & ')' AS [Course Owner]

Answer 1

You are missing two closing parentheses...and I am not sure an ampersand works as a string concatenation operator. Try '+'
SELECT dbo.COL_V_Cost_GEMS_Detail.TNG_SYS_NR AS [EHP Code],
dbo.COL_TBL_VCOURSE.TNG_NA AS [Course Title],
LTRIM(RTRIM(FCT_TYP_CD)) + ') AND (' + LTRIM(RTRIM(DEP_TYP_ID)) + ')' AS [Course Owner]

Answer 2

TRIM all SPACE's TAB's and ENTER's:
DECLARE #Str VARCHAR(MAX) = '
[ Foo ]
'
DECLARE #NewStr VARCHAR(MAX) = ''
DECLARE #WhiteChars VARCHAR(4) =
CHAR(13) + CHAR(10) -- ENTER
+ CHAR(9) -- TAB
+ ' ' -- SPACE
;WITH Split(Chr, Pos) AS (
SELECT
SUBSTRING(#Str, 1, 1) AS Chr
, 1 AS Pos
UNION ALL
SELECT
SUBSTRING(#Str, Pos, 1) AS Chr
, Pos + 1 AS Pos
FROM Split
WHERE Pos <= LEN(#Str)
)
SELECT #NewStr = #NewStr + Chr
FROM Split
WHERE
Pos >= (
SELECT MIN(Pos)
FROM Split
WHERE CHARINDEX(Chr, #WhiteChars) = 0
)
AND Pos <= (
SELECT MAX(Pos)
FROM Split
WHERE CHARINDEX(Chr, #WhiteChars) = 0
)
SELECT '"' + #NewStr + '"'
As Function
CREATE FUNCTION StrTrim(#Str VARCHAR(MAX)) RETURNS VARCHAR(MAX) BEGIN
DECLARE #NewStr VARCHAR(MAX) = NULL
IF (#Str IS NOT NULL) BEGIN
SET #NewStr = ''
DECLARE #WhiteChars VARCHAR(4) =
CHAR(13) + CHAR(10) -- ENTER
+ CHAR(9) -- TAB
+ ' ' -- SPACE
IF (#Str LIKE ('%[' + #WhiteChars + ']%')) BEGIN
;WITH Split(Chr, Pos) AS (
SELECT
SUBSTRING(#Str, 1, 1) AS Chr
, 1 AS Pos
UNION ALL
SELECT
SUBSTRING(#Str, Pos, 1) AS Chr
, Pos + 1 AS Pos
FROM Split
WHERE Pos <= LEN(#Str)
)
SELECT #NewStr = #NewStr + Chr
FROM Split
WHERE
Pos >= (
SELECT MIN(Pos)
FROM Split
WHERE CHARINDEX(Chr, #WhiteChars) = 0
)
AND Pos <= (
SELECT MAX(Pos)
FROM Split
WHERE CHARINDEX(Chr, #WhiteChars) = 0
)
END
END
RETURN #NewStr
END
Example
-- Test
DECLARE #Str VARCHAR(MAX) = '
[ Foo ]
'
SELECT 'Str', '"' + dbo.StrTrim(#Str) + '"'
UNION SELECT 'EMPTY', '"' + dbo.StrTrim('') + '"'
UNION SELECT 'EMTPY', '"' + dbo.StrTrim(' ') + '"'
UNION SELECT 'NULL', '"' + dbo.StrTrim(NULL) + '"'
Result
+-------+----------------+
| Test | Result |
+-------+----------------+
| EMPTY | "" |
| EMTPY | "" |
| NULL | NULL |
| Str | "[ Foo ]" |
+-------+----------------+

Answer 3

LTRIM(RTRIM(FCT_TYP_CD)) & ') AND (' & LTRIM(RTRIM(DEP_TYP_ID)) & ')'
I think you're missing a ) on both of the trims. Some SQL versions support just TRIM which does both L and R trims...

Answer 4

Example:
DECLARE #Str NVARCHAR(MAX) = N'
foo bar
Foo Bar
'
PRINT '[' + #Str + ']'
DECLARE #StrPrv NVARCHAR(MAX) = N''
WHILE ((#StrPrv <> #Str) AND (#Str IS NOT NULL)) BEGIN
SET #StrPrv = #Str
-- Beginning
IF EXISTS (SELECT 1 WHERE #Str LIKE '[' + CHAR(13) + CHAR(10) + CHAR(9) + ']%')
SET #Str = LTRIM(RIGHT(#Str, LEN(#Str) - 1))
-- Ending
IF EXISTS (SELECT 1 WHERE #Str LIKE '%[' + CHAR(13) + CHAR(10) + CHAR(9) + ']')
SET #Str = RTRIM(LEFT(#Str, LEN(#Str) - 1))
END
PRINT '[' + #Str + ']'
Result
[
foo bar
Foo Bar
]
[foo bar
Foo Bar]
Using fnTrim
Source: https://github.com/reduardo7/fnTrim
SELECT dbo.fnTrim(colName)