In my database I should only have data written using Polish alphabet but sometimes there are symbols not included in Polish alphabet (words copied from source with different encoding) that correspond to Polish letters in another encoding. Is it possible to somehow convert symbols outside of Polish alphabet to corresponding letters?
The only solution I figured is to manually find and replace those characters but maybe you have better solution to my problem.
Question concerns Oracle SQL Language.
I don't have database in front of me but as I remember correctly the example could look like this - two rows from my db:
ŚWIAT
ÚWIAT
and what I need is to convert Ú that doesn't belong to Polish alphabet to Ś.
You can try this. Experiment with it first to see if it works.
If I want to change every occurrence of the letter z with a j in a string, I would use the translate function: translate(text_string, 'z', 'j'). I don't have to use the letters z and j; instead, I can write translate(text_string, chr(122), chr(106) - to find out the character code, I use select ascii('z') from dual;. For example:
SQL> select translate('banzo', chr(122), chr(106)) from dual;
TRANS
-----
banjo
This changes every occurrence of z to j in text_string.
Now, you will have to find the code for the characters you want to change (both the "from" and the "to" characters) in your character set - it should be your session character set, not the database character set. (At least I think this is correct; experiment with it or read the documentation for CHR and perhaps for TRANSLATE - CHR returns the character code in the DATABASE character set unless you indicate otherwise, while I believe TRANSLATE uses the session character set.)
The function ascii may or may not work for non-ASCII characters, but if you google the name of your character set, you should find a character set table that will show you the codes for all the letters available in that character set.
Then, if this works, you can do the translation in one shot - translate(text_string, 'abcd', 'qrst') will change every 'a' to a 'q', every 'b' to an 'r' etc. And with chr(...), instead of 'abcd' you can write chr(97) || chr(98) || chr(99) || chr(100).
Related
When trying to remove all accents from a string in Oracle using the techniques described in this stackoverflow answer: how replace accented letter in a varchar2 column in oracle I’m getting mixed results.
select CONVERT('JUAN ROMÄN', 'US7ASCII') from dual;
Returns the original string but replaces characters with for example ñ by a question mark (probably because of the chosen charset - tests with different charsets led to different results).
Using the following technique:
select utl_raw.cast_to_varchar2(nlssort(NAME_USER, 'nls_sort=binary_ai')) from YOUR_TABLE;
Returns the complete string but also places a NUL value at the end of the string.
Is there a characterset that I can use with Spanish accents to get a correct result (the original string with the different accents removed); is there a way to avoid the NUL value in the utl_raw.cast_to_varchar2 technique?
Based on the comments the the replace char(0) seems to remove the NUL value. For example
select
upper(utl_raw.cast_to_varchar2((nlssort('this is áà ñew test','nls_sort=binary_ai')))) as test,
replace(upper(utl_raw.cast_to_varchar2((nlssort('this is áà ñew test','nls_sort=binary_ai')))),chr(0),'') as test2
from dual;
If possible I would however to have a more 'straightforward/simpler' solution.
You can use TRANSLATE(your_string, from_chars, to_chars) https://docs.oracle.com/cd/B19306_01/server.102/b14200/functions196.htm
Just put all chars with accents in from_chars string and their corresponding replacement chars in to_chars.
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.
I need to use SQL to find a sequence of characters at a specific position in a string.
Example:
atcgggatgccatg
I need to find 'atg' starting at character 7 or at character 7-9, either way would work. I don't want to find the 'atg' at the end of the string. I know about LIKE but couldn't find how to use it for a specific position.
Thank you
In MS Access, you could write this as:
where col like '???????atg*' or
col like '????????atg*' or
col like '?????????atg*'
However, if you interested in this type of comparison, you might consider using a database that supports regular expressions.
If you have a look at this page you'll find that LIKE is entirely capable of doing what you want. To find something at, for example, a 3 char offset you can use something like this
SELECT * FROM SomeTable WHERE [InterestingField] LIKE '___FOO%'
The '_' (underscore) is a place marker for any char. Having 3 "any char" markers in the pattern, with a trailing '%', means that the above SQL will match anything with FOO starting from the fourth char, and then anything else (including nothing).
To look for something 7 chars in, use 7 underscores.
Let me know ifthis isn't quite clear.
EDIT: I quoted SQL Server stuff, not Access. Swap in '?' where I have '_', use '*' instead of '%', and check out this link instead.
Revised query:
SELECT * FROM SomeTable WHERE [InterestingField] LIKE '???FOO*'
I'm trying to implement stuff similar to spell check, but I need to get the word that is limited by a space. EX: "HI HOW R U", I need to collect HI, HOW and so on as they type. i.e. After user hits HI and space I need to collect HI and do a spell check.
Check the documentation for NSString Here. You want the message componentsSepeparatedByString:.
I don't know objective-C, but I'm fairly sure it'll have a Regexp library - although it'd be straightforward to code it without one.
Regexp: \b([^\s])*\b
\b = word boundary (whitespace, comma, dot, exclamation-mark, etc.)
\s = whitespace character
[...] = character set
[^...] = negated character set (any character(s) EXCEPT ...)
() = grouping construct
* = zero or more times
So the suggested expression would start matching at any word boundary, then match every subsequent character that is not a whitespace character, then match a word boundary.
Your stated case is so simple you may just want to look for spaces (one char at a time) and get the substring, but RegExp is very widely used across a range of languages and platforms, and so it's fairly easy to find an expression when you need to - and one often does for common stuff like checking if zip codes, phone numbers, email addresses and so on are syntactically correct. So it's worth learning in any case. :)
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