I need to find and clean up line breaks, carriage returns, tabs and "SUB"-characters in a set of 400k+ string records, but this DB2 environment is taking a toll on me.
Thought I could do some search and replacing with the REPLACE() and CHR() functions, but it seems CHR() is not available on this system (Error: CHR in *LIBL type *N not found). Working with \t, \r, \n etc doesn't seem to be working either. The chars can be in the middle of strings or at the end of them.
DBMS = DB2
System = iSeries
Language = SQL
Encoding = Not sure, possibly EBCDIC
Any hints on what I can do with this?
I used this SQL to find x'25' and x'0D':
SELECT
<field>
, LOCATE(x'0D', <field>) AS "0D"
, LOCATE(x'25', <field>) AS "25"
, length(trim(<field>)) AS "Length"
FROM <file>
WHERE LOCATE(x'25', <field>) > 0
OR LOCATE(x'0D', <field>) > 0
And I used this SQL to replace them:
UPDATE <file>
SET <field> = REPLACE(REPLACE(<field>, x'0D', ' '), x'25', ' ')
WHERE LOCATE(x'25', <field>) > 0
OR LOCATE(x'0D', <field>) > 0
If you want to clear up specific characters like carriage return (EBCDIC x'0d') and line feed (EBCDIC x'25') you should find the translated character in EBCDIC then use the TRANSLATE() function to replace them with space.
If you just want to remove undisplayable characters then look for anything under x'40'.
Here is an sample script that replaces X'41' by X'40'. Something that was creating issues at our shop:
UPDATE [yourfile] SET [yourfield] = TRANSLATE([yourfield], X'40',
X'41') WHERE [yourfield] like '%' concat X'41' concat '%'
If you need to replace more than one character, extend the "to" and "from" hexadecimal strings to the values you need in the TRANSLATE function.
Try TRANSLATE or REPLACE.
The brute force method involves using POSITION to find the errant character, then SUBSTR before and after it. CONCAT the two substrings (less the undesirable character) to re-form the column.
The character encoding is almost certainly one of the EBCDIC character sets. Depending on how the table got loaded in the first place, the CR may be x'0d' and the LF x'15', x'25'. An easy way to find out is to get to a green screen and do a DSPPFM against the table. Press F10 then F11 to view the table is raw, hexadecimal (over/under) format.
For details on the available functions see the
DB2 for i5/OS SQL Reference.
Perhaps the TRANSLATE() function will serve your needs.
TRANSLATE( data, tochars, fromchars )
...where fromchars is the set of characters you don't want, and tochars is the corresponding characters you want them replaced with. You may have to write this out in hex format, as x'nnnnnn...' and you will need to know what character set you are working with.
Using the DSPFFD command on your table should show the CCSID of your fields.
we struggled a lot to replace the new line char and carriage return from flat file.
Finally we used below sql to sort the issue.
REPLACE(REPLACE(COLUMN_NAME, CHR(13), ''), CHR(10), '')
Try it out
CR = CHR(13)
LF = CHR(10)
Related
I got the following entry in my database with column name - properties_desc:
#Thu Sep 03 02:18:11 UTC 2020 cardType=MasterCard cardDebit=true cardUniqueNumber=f0b03da93bc70fbc194a5a4ef5879685
I want to trim the entry so I get: MasterCard
So basically, I want everything after 'cardType=' and before ''.
I tried referring this Get everything after and before certain character in SQL Server
but this works for a special character and not a string.
My try:
SUBSTRING(properties_desc, length(SUBSTRING(properties_desc, 0, length(properties_desc) - CHARINDEX ('cardType=', properties_desc))) + 1,
length(properties_desc) - length(SUBSTRING(properties_desc, 0, length(properties_desc) - CHARINDEX ('cardType=', properties_desc))) - length(SUBSTRING(
properties_desc, CHARINDEX (' ', properties_desc), length(properties_desc))))
But the above query does not work. Any help is appreciated.
How can I solve it?
You have tagged this question as both sql-server and databricks. Based on your use of length() instead of len(), I assume that you are using databricks. In that case, you can make use of the regexp_extract() function
Try: "regexp_extract(properties_desc, '(?<=cardType=)[^ ]*')".
This is untested, as I am not a databricks programmer.
The "[^ ]*" in the above will match and extract a string of non-space characters after "cardType=". The "(?<=...)" is a "look-behind" construct that requires that the matched text be preceded by "cardType=", but does not include that text in the result. The end result is that the regex matches and extracts everything after "cardtype=" up to the next space (or the end of the string).
Regular expressions are a pretty powerful string matching tool. Well worth learning if you are not already familiar with them. (I wish SQL Server had them.)
Based on my research so far this character indicates bad encoding between the database and front end. Unfortunately, I don't have any control over either of those. I'm using Teradata Studio.
How can I filter this character out? I'm trying to perform a REGEX_SUBSTR function on a column that occasionally contains �, which throws the error "The string contains an untranslatable character".
Here is my SQL. AIRCFT_POSITN_ID is the column that contains the replacement character.
SELECT DISTINCT AIRCFT_POSITN_ID,
REGEXP_SUBSTR(AIRCFT_POSITN_ID, '[0-9]+') AS AUTOROW
FROM PROD_MAE_MNTNC_VW.FMR_DISCRPNCY_DFRL
WHERE DFRL_CREATE_TMS > CURRENT_DATE -25
Your diagnostic is correct, so first of all, you might want to check the Session Character Set (it is part of the connection definition).
If it is ASCII change it to UTF8 and you will be able to see the original characters instead of the substitute character.
And in case the character is indeed part of the data and not just an indication for encoding translations issues:
The substitute character AKA SUB (DEC: 26 HEX: 1A) is quite unique in Teradata.
you cannot use it directly -
select '�';
-- [6706] The string contains an untranslatable character.
select '1A'XC;
-- [6706] The string contains an untranslatable character.
If you are using version 14.0 or above you can generate it with the CHR function:
select chr(26);
If you're below version 14.0 you can generate it like this:
select translate (_unicode '05D0'XC using unicode_to_latin with error);
Once you have generated the character you can now use it with REPLACE or OTRANSLATE
create multiset table t (i int,txt varchar(100) character set latin) unique primary index (i);
insert into t (i,txt) values (1,translate ('Hello שלום world עולם' using unicode_to_latin with error));
select * from t;
-- Hello ���� world ����
select otranslate (txt,chr(26),'') from t;
-- Hello world
select otranslate (txt,translate (_unicode '05D0'XC using unicode_to_latin with error),'') from t;
-- Hello world
BTW, there are 2 versions for OTRANSLATE and OREPLACE:
The functions under syslib works with LATIN.
the functions under TD_SYSFNLIB works with UNICODE.
In addition to Dudu's excellent answer above, I wanted to add the following now that I've encountered the issue again and had more time to experiment. The following SELECT command produced an untranslatable character:
SELECT IDENTIFY FROM PROD_MAE_MNTNC_VW.SCHD_MNTNC;
IDENTIFY
24FEB1747659193DC330A163DCL�ORD
Trying to perform a REGEXP_REPLACE or OREPLACE directly on this character produces an error:
Failed [6706 : HY000] The string contains an untranslatable character.
I changed the CHARSET property in my Teradata connection from UTF8 to ASCII and I could now see the offending character, looks like a tab
IDENTIFY
Using the TRANSLATE_CHK command using this specific conversion succeeds and identifies the position of the offending character (Note that this does not work using the UTF8 charset):
TRANSLATE_CHK(IDENTIFY USING KANJI1_SBC_TO_UNICODE) AS BADCHAR
BADCHAR
28
Now this character can be dealt with using some CASE statements to remove the bad character and retain the remainder of the string:
CASE WHEN TRANSLATE_CHK(IDENTIFY USING KANJI1_SBC_TO_UNICODE) = 0 THEN IDENTIFY
ELSE SUBSTR(IDENTIFY, 1, TRANSLATE_CHK(IDENTIFY USING KANJI1_SBC_TO_UNICODE)-1)
END AS IDENTIFY
Hopes this helps someone out.
This question already has answers here:
SQL query for a carriage return in a string and ultimately removing carriage return
(10 answers)
Closed 8 years ago.
Facing a problem, it seems my data stored in SQL Server does not stored correctly, simply put, how to verify that a varchar data has carriage return and line feed in it? I try to print them out, does not show the special characters.
Thanks
You can use SQL Server's char(n) and contains() functions to match on field contents in your WHERE clause.
carriage return: char(13)
line feed: char(10)
The following SQL will find all rows in some_table where the values of some_field contain newline and/or carriage return characters:
SELECT * FROM some_table
WHERE CONTAINS(some_field, char(13)) OR CONTAINS(some_field, char(10))
To remove carriage returns in your some_field values you could use the replace() function long with char() and contains(). The SQL would look something like:
UPDATE some_table
SET some_field = REPLACE(some_field, char(13), '')
WHERE CONTAINS(some_field, char(13))
To remove new lines you can follow up the last statement with the char(10) version of that update. How you do it all depends on what types of newlines your text contains. But, depending on where the text was inserted/pasted from the new lines may be \r\n or \n so running updates against both \r and \n characters would be safer than assuming that you're getting one version of newline or the other.
Note that if the newlines were removed and you want to retain them then you have to fix the issue at the point of entry. You can't replace or fix what has been removed so you should save the original text data in a new column that holds the original, unmodified text.
To add to what others have said; when I need to embed newlines in T-SQL, I tend to do;
DECLARE #nl CHAR(2) = CHAR(13) + CHAR(10);
..then use #nl as required. That's for Windows line-endings, naturally.
Take a look at the Char function. See MSDN. This will help look for the special characters.
I am having some rows in table with some unusual character. When I use ascii() or unicode() for that character, it returns 63. But when I try this -
update MyTable
set MyColumn = replace(MyColumn,char(63),'')
it does not replace. The unusual character still exists after the replace function. Char(63) incidentally looks like a question mark.
For example my string is 'ddd#dd ddd' where # it's my unusual character and
select unicode('#')
return me 63.But this code
declare #str nvarchar(10) = 'ddd#dd ddd'
set #char = char(unicode('#'))
set #str = replace(#str,#char,'')
is working!
Any ideas how to resolve this?
Additional information:
select ascii('�') returns 63, and so does select ascii('?'). Finally select char(63) returns ? and not the diamond-question-mark.
When this character is pasted into Excel or a text editor, it looks like a space, but in an SQL Server Query window (and, apparently, here on StackOverflow as well), it looks like a diamond containing a question mark.
Not only does char(63) look like a '?', it is actually a '?'.
(As a simple test ensure you have numlock on your keyboard on, hold down the alt key andtype '63' into the number pad - you can all sorts of fun this way, try alt-205, then alt-206 and alt-205 again: ═╬═)
Its possible that the '?' you are seeing isn't a char(63) however, and more indicitive of a character that SQL Server doesn't know how to display.
What do you get when you run:
select ascii(substring('[yourstring]',[pos],1));
--or
select unicode(substring('[yourstring]',[pos],1));
Where [yourstring] is your string and [pos] is the position of your char in the string
EDIT
From your comment it seems like it is a question mark. Have you tried:
replace(MyColumn,'?','')
EDIT2
Out of interest, what does the following do for you:
replace(replace(MyColumn,char(146),''),char(63),'')
char(63) is a question mark. It sounds like these "unusual" characters are displayed as a question mark, but are not actually characters with char code 63.
If this is the case, then removing occurrences of char(63) (aka '?') will of course have no effect on these "unusual" characters.
I believe you actually didn't have issues with literally CHAR(63), because that should be just a normal character and you should be able to properly work with it.
What I think happened is that, by mistake, an UTF character (for example, a cyrilic "А") was inserted into the table - and either your:
columns setup,
the SQL code,
or the passed in parameters
were not prepared for that.
In this case, the sign might be visible to you as ?, and its CHAR() function would actually give 63, but you should really use the NCHAR() to figure out the real code of it.
Let me give a specific example, that I had multiple times - issues
with that Cyrilic "А", which looks identical to the Latin one, but has
a unicode of 1040.
If you try to use the non-UTF CHAR function on that 1040 character,
you would get a code 63, which is not true (and is probably just an
info about the first byte of multibyte character).
Actually, run this to make the differences in my example obvious:
SELECT NCHAR(65) AS Latin_A, NCHAR(1040) Cyrilic_A, ASCII(NCHAR(1040)) Latin_A_Code, UNICODE(NCHAR(1040)) Cyrilic_A_Code;
That empty string Which shows us '?' in substring.
Gives us Ascii value as 63.
It's a Zero Width space which gets appended if you copy data from ui and insert into the database.
To replace the data, you can use below query
**set MyColumn = replace(MyColumn,NCHAR(8203),'')**
It's an older question, but I've run into this problem as well. I found the solution somewhere else on internet, but I thought it would be good to share it here as well. Have a good day.
Replace(YourString, nchar(65533) COLLATE Latin1_General_BIN2, '')
This should work as well:
UPDATE TABLE
SET [FieldName] = SUBSTRING([FieldName], 2, LEN([FieldName]))
WHERE ASCII([FieldName]) = 63
I have a Sql statament using special character (ex: ('), (/), (&)) and I don't know how to write them in my VB.NET code. Please help me. Thanks.
Find out the Unicode code point for the character (from http://www.unicode.org) and then use ChrW to convert from the code point to the character. (To put this in another string, use concatenation. I'm somewhat surprised that VB doesn't have an escape sequence, but there we go.)
For example, for the Euro sign (U+20AC) you'd write:
Dim euro as Char = ChrW(&H20AC)
The advantage of this over putting the character directly into source code is that your source code stays "just pure ASCII" - which means you won't have any strange issues with any other program trying to read it, diff it, etc. The disadvantage is that it's harder to see the symbol in the code, of course.
The most common way seems to be to append a character of the form Chr(34)... 34 represents a double quote character. The character codes can be found from the windows program "charmap"... just windows/Run... and type charmap
If you are passing strings to be processed as SQL statement try doubling the characters for example.
"SELECT * FROM MyRecords WHERE MyRecords.MyKeyField = ""With a "" Quote"" "
The '' double works with the other special characters as well.
The ' character can be doubled up to allow it into a string e.g
lSQLSTatement = "Select * from temp where name = 'fred''s'"
Will search for all records where name = fred's
Three points:
1) The example characters you've given are not special characters. They're directly available on your keyboard. Just press the corresponding key.
2) To type characters that don't have a corresponding key on the keyboard, use this:
Alt + (the ASCII code number of the special character)
For example, to type ¿, press Alt and key in 168, which is the ASCII code for that special character.
You can use this method to type a special character in practically any program not just a VB.Net text editor.
3) What you probably looking for is what is called 'escaping' characters in a string. In your SQL query string, just place a \ before each of those characters. That should do.
Chr() is probably the most popular.
ChrW() can be used if you want to generate unicode characters
The ControlChars class contains some special and 'invisible' characters, plus the quote - for example, ControlChars.Quote