Why ignoring space text in SQL Server 2014 - sql

When I compared text like this:
'a' = 'a '
the result is True - but I was expecting it to be false.
Do you know why the result is true? And can I do something to solve this issue?


The LIKE operator does not pad the trailing spaces:
SELECT * FROM basePath WHERE 'a' LIKE 'a '
More information can be found here: https://dba.stackexchange.com/questions/56876/sql-server-auto-trim-of-varchar-value-in-equal-comparison-but-not-like-compariso


You can use DATALENGTH()
Example
SELECT * FROM TableName WHERE DATALENGT('a') = DATALENGTH('a ')
DATALENGT('a') return the result as 1
and DATALENGTH('a ') return the result as 2, includes the space text.
Please check the db<>fiddle for reference.

Related

Can't remove Trailing spaces in the rows

I have column with data like:
'2020193'
'3208391'
'1038291'
'9349203'
The data type is varchar and I can't change it to int (data managed in this datatype always).
I have some rows with trailing spaces like:
' 2222928'
' 3213331'
I need to remove that trailing space from start. I have tried SUBSTRING() or TRIM()/RTRIM()/LTRIM(), but didn't worked any of those.
select (rtrim(ltrim(doc_id))) from bpm.sales where len(doc_id) = 8
select left(doc_id,2) from bpm.sales where len(doc_id) = 8
select charindex(' ',doc_id) from bpm.sales where len(doc_id) = 8
Also, when I am trying to search the data like:
select doc_id from bpm.sales where doc_id = ' 2269203'
I am geting nothing where it exist in the column. With CHARINDEX() I got 0.
Can someone explain me this behaviour and suggest a solution?

You can get rid of everything up to the first character you do want:
select stuff(doc_id, 1, patindex('%[^0-9a-zA-Z]%', doc_id) - 1, '')

Biq Query regex_replace error (\? vs \\?)

I am having issues understanding what's wrong with this regex: \?.*
select REGEXP_REPLACE(longstringcolumn, '\?.*', '') as newstring from tablename
My example string aka 'longstring' has '?' character, and I am trying to match everything trailing '?' (including '?' itself).
I have checked my regexpr in online tools and my regex seems to be working.
Edit
Thanks guys for being so quick,
Here's a sample string (it's a url):
http://example.com/one/two/three?lang=en&region=CN
I am trying to strip off everything after '?'. So this part:
?lang=en&region=CN
This is the error I am being returned: Failed to parse regular expression "?": no argument for repetition operator: ?
I am really leaning towards this being a simple escape character issue but I can't figure it out somehow.

#standardSQL
SELECT REGEXP_REPLACE(longstringcolumn, '\\?.*', '') AS newstring
FROM tablename
or
#standardSQL
SELECT REGEXP_REPLACE(longstringcolumn, r'\?.*', '') AS newstring
FROM tablename
example below
#standardSQL
WITH tablename AS (
SELECT 'is this a question?abc ' AS longstringcolumn UNION ALL
SELECT 'this is not a question' union all
SELECT'http://example.com/one/two/three?lang=en&region=CN'
)
SELECT REGEXP_REPLACE(longstringcolumn, r'\?.*', '') AS newstring
FROM tablename
with result as (where ? and all trailing chars are removed)
Row newstring
1 is this a question
2 this is not a question
Hope this shows what was wrong with your original query

SQL: How to make a replace on the field ''

I have a very but tricky question for you guys. So, listen I have a field with spaces and numbers in one of my table columns. The key part is transform the content in a decimal field. The drawback is basically that for some rows I could get something like:
' 1584.00 '
' 156546'
'545.00 '
' '
So, to clean up my column, I have done a LTRIM and RTRIM so spaces gone. So now for a couple of records where the record were just spaces the new content is ''. Finally I need to convert this result to a decimal.
Issue: The thing is that for field that contend just the spaces the new result is '' and I'm not able to apply a REPLACE on this because it's a blank and the code below doesn't work:
SELECT REPLACE('','','0')
-- Final current verison
SELECT CAST(COALESCE(REPLACE(REPLACE([Gross_Weight],' ','0'),',',''),'0') AS DECIMAL(13,3))
How could I figure it out?
thanks so much

SELECT COALESCE(NULLIF(MyColumn, ''), 0)
This has the side-effect that you will also turn NULL values into 0, which you might not want. If that's a problem then a simple CASE statement should do the trick:
SELECT CASE WHEN MyColumn = '' THEN 0 ELSE CAST(MyColumn AS DECIMAL(10, 4)) END
Obviously you'll also have to incorporate any other manipulations that you're already doing.

No need for replace, just concatenate a zero to your column, like
SELECT RTRIM('0' + LTRIM(column))

I presume your data is in a table.
Lets call this table 'DATA' and the column 'VALUE'
Then you might use the below query
UPDATE DATA SET VALUE = 0 where VALUE = ''
To select the value do the below
select case ltrim(rtrim([Gross_Weight])) when ''
THEN 0
ELSE ltrim(rtrim([Gross_Weight])) END
Let me know if i get the requirement wrong.

Detect \n character saved in SQLite table?

I designed a table with a column whose data contains \n character (as the separator, I used this instead of comma or anything else). It must save the \n characters OK because after loading the table into a DataTable object, I can split the values into arrays of string with the separator '\n' like this:
DataTable dt = LoadTable("myTableName");
DataRow dr = dt.Rows[0]; //suppose this row has the data with \n character.
string[] s = dr["myColumn"].ToString().Split(new char[]{'\n'}, StringSplitOptions.RemoveEmptyEntries);//This gives result as I expect, e.g an array of 2 or 3 strings depending on what I saved before.
That means '\n' does exist in my table column. But when I tried selecting only rows which contain \n character at myColumn, it gave no rows returned, like this:
--use charindex
SELECT * FROM MyTable WHERE CHARINDEX('\n',MyColumn,0) > 0
--use like
SELECT * FROM MyTable WHERE MyColumn LIKE '%\n%'
I wonder if my queries are wrong?
I've also tested with both '\r\n' and '\r' but the result was the same.
How can I detect if the rows contain '\n' character in my table? This is required to select the rows I want (this is by my design when choosing '\n' as the separator).
Thank you very much in advance!

Since \n is the ASCII linefeed character try this:
SELECT *
FROM MyTable
WHERE MyColumn LIKE '%' || X'0A' || '%'
Sorry this is just a guess; I don't use SQLite myself.

Maybe you should just be looking for carriage returns if you arent storing the "\n" literal in the field. Something like
SELECT *
FROM table
WHERE column LIKE '%
%'
or select * from table where column like '%'+char(13)+'%' or column like '%'+char(10)+'%'
(Not sure if char(13) and 10 work for SQLite
UPDATED: Just found someone's solution here They recommend to replace the carriage returns
So if you want to replace them and strip the returns, you could
update yourtable set yourCol = replace(yourcol, '
', ' ');

The following should do it for you
SELECT *
FROM your_table
WHERE your_column LIKE '%' + CHAR(10) + '%'
If you want to test for carriage return use CHAR(13) instead or combine them.

I've found a solution myself. There is few way (with some dedicated function) to convert ascii code to symbol in SQLite at the moment (CHAR function is not support and using '\n' or '\r' directly doesn't work). But we can convert using CAST function and passing in a Hex string (specified by append X or x before the string) in SQLite like this:
-- use CHARINDEX
SELECT * FROM MyTable WHERE CHARINDEX(CAST(x'0A' AS text),MyColumn,0) > 0
-- use LIKE
SELECT * FROM MyTable WHERE MyColumn LIKE '%' || CAST(x'0A' AS text) || '%'
The Hex string '0A' is equal to 10 in ascii code (\r). I've tried with '0D' (13 or '\n') but it won't work. Maybe the \n character is turned to \r after being saved in to SQLite table.
Hope this helps others! Thanks!

How can I remove leading and trailing quotes in SQL Server?

I have a table in a SQL Server database with an NTEXT column. This column may contain data that is enclosed with double quotes. When I query for this column, I want to remove these leading and trailing quotes.
For example:
"this is a test message"
should become
this is a test message
I know of the LTRIM and RTRIM functions but these workl only for spaces. Any suggestions on which functions I can use to achieve this.

I have just tested this code in MS SQL 2008 and validated it.
Remove left-most quote:
UPDATE MyTable
SET FieldName = SUBSTRING(FieldName, 2, LEN(FieldName))
WHERE LEFT(FieldName, 1) = '"'
Remove right-most quote: (Revised to avoid error from implicit type conversion to int)
UPDATE MyTable
SET FieldName = SUBSTRING(FieldName, 1, LEN(FieldName)-1)
WHERE RIGHT(FieldName, 1) = '"'

I thought this is a simpler script if you want to remove all quotes
UPDATE Table_Name
SET col_name = REPLACE(col_name, '"', '')

You can simply use the "Replace" function in SQL Server.
like this ::
select REPLACE('this is a test message','"','')
note: second parameter here is "double quotes" inside two single quotes and third parameter is simply a combination of two single quotes. The idea here is to replace the double quotes with a blank.
Very simple and easy to execute !

My solution is to use the difference in the the column values length compared the same column length but with the double quotes replaced with spaces and trimmed in order to calculate the start and length values as parameters in a SUBSTRING function.
The advantage of doing it this way is that you can remove any leading or trailing character even if it occurs multiple times whilst leaving any characters that are contained within the text.
Here is my answer with some test data:
SELECT
x AS before
,SUBSTRING(x
,LEN(x) - (LEN(LTRIM(REPLACE(x, '"', ' ')) + '|') - 1) + 1 --start_pos
,LEN(LTRIM(REPLACE(x, '"', ' '))) --length
) AS after
FROM
(
SELECT 'test' AS x UNION ALL
SELECT '"' AS x UNION ALL
SELECT '"test' AS x UNION ALL
SELECT 'test"' AS x UNION ALL
SELECT '"test"' AS x UNION ALL
SELECT '""test' AS x UNION ALL
SELECT 'test""' AS x UNION ALL
SELECT '""test""' AS x UNION ALL
SELECT '"te"st"' AS x UNION ALL
SELECT 'te"st' AS x
) a
Which produces the following results:
before after
-----------------
test test
"
"test test
test" test
"test" test
""test test
test"" test
""test"" test
"te"st" te"st
te"st te"st
One thing to note that when getting the length I only need to use LTRIM and not LTRIM and RTRIM combined, this is because the LEN function does not count trailing spaces.

I know this is an older question post, but my daughter came to me with the question, and referenced this page as having possible answers. Given that she's hunting an answer for this, it's a safe assumption others might still be as well.
All are great approaches, and as with everything there's about as many way to skin a cat as there are cats to skin.
If you're looking for a left trim and a right trim of a character or string, and your trailing character/string is uniform in length, here's my suggestion:
SELECT SUBSTRING(ColName,VAR, LEN(ColName)-VAR)
Or in this question...
SELECT SUBSTRING('"this is a test message"',2, LEN('"this is a test message"')-2)
With this, you simply adjust the SUBSTRING starting point (2), and LEN position (-2) to whatever value you need to remove from your string.
It's non-iterative and doesn't require explicit case testing and above all it's inline all of which make for a cleaner execution plan.

The following script removes quotation marks only from around the column value if table is called [Messages] and the column is called [Description].
-- If the content is in the form of "anything" (LIKE '"%"')
-- Then take the whole text without the first and last characters
-- (from the 2nd character and the LEN([Description]) - 2th character)
UPDATE [Messages]
SET [Description] = SUBSTRING([Description], 2, LEN([Description]) - 2)
WHERE [Description] LIKE '"%"'

You can use following query which worked for me-
For updating-
UPDATE table SET colName= REPLACE(LTRIM(RTRIM(REPLACE(colName, '"', ''))), '', '"') WHERE...
For selecting-
SELECT REPLACE(LTRIM(RTRIM(REPLACE(colName, '"', ''))), '', '"') FROM TableName

you could replace the quotes with an empty string...
SELECT AllRemoved = REPLACE(CAST(MyColumn AS varchar(max)), '"', ''),
LeadingAndTrailingRemoved = CASE
WHEN MyTest like '"%"' THEN SUBSTRING(Mytest, 2, LEN(CAST(MyTest AS nvarchar(max)))-2)
ELSE MyTest
END
FROM MyTable

Some UDFs for re-usability.
Left Trimming by character (any number)
CREATE FUNCTION [dbo].[LTRIMCHAR] (#Input NVARCHAR(max), #TrimChar CHAR(1) = ',')
RETURNS NVARCHAR(max)
AS
BEGIN
RETURN REPLACE(REPLACE(LTRIM(REPLACE(REPLACE(#Input,' ','¦'), #TrimChar, ' ')), ' ', #TrimChar),'¦',' ')
END
Right Trimming by character (any number)
CREATE FUNCTION [dbo].[RTRIMCHAR] (#Input NVARCHAR(max), #TrimChar CHAR(1) = ',')
RETURNS NVARCHAR(max)
AS
BEGIN
RETURN REPLACE(REPLACE(RTRIM(REPLACE(REPLACE(#Input,' ','¦'), #TrimChar, ' ')), ' ', #TrimChar),'¦',' ')
END
Note the dummy character '¦' (Alt+0166) cannot be present in the data (you may wish to test your input string, first, if unsure or use a different character).

To remove both quotes you could do this
SUBSTRING(fieldName, 2, lEN(fieldName) - 2)
you can either assign or project the resulting value

You can use TRIM('"' FROM '"this "is" a test"') which returns: this "is" a test

CREATE FUNCTION dbo.TRIM(#String VARCHAR(MAX), #Char varchar(5))
RETURNS VARCHAR(MAX)
BEGIN
RETURN SUBSTRING(#String,PATINDEX('%[^' + #Char + ' ]%',#String)
,(DATALENGTH(#String)+2 - (PATINDEX('%[^' + #Char + ' ]%'
,REVERSE(#String)) + PATINDEX('%[^' + #Char + ' ]%',#String)
)))
END
GO
Select dbo.TRIM('"this is a test message"','"')
Reference : http://raresql.com/2013/05/20/sql-server-trim-how-to-remove-leading-and-trailing-charactersspaces-from-string/

I use this:
UPDATE DataImport
SET PRIO =
CASE WHEN LEN(PRIO) < 2
THEN
(CASE PRIO WHEN '""' THEN '' ELSE PRIO END)
ELSE REPLACE(PRIO, '"' + SUBSTRING(PRIO, 2, LEN(PRIO) - 2) + '"',
SUBSTRING(PRIO, 2, LEN(PRIO) - 2))
END

Try this:
SELECT left(right(cast(SampleText as nVarchar),LEN(cast(sampleText as nVarchar))-1),LEN(cast(sampleText as nVarchar))-2)
FROM TableName