SQLITE Query question:
I have a query which returns string with the character '#' in it.
I would like to remove all characters after this specific character '#':
select field from mytable;
result :
text#othertext
text2#othertext
text3#othertext
So in my sample I would like to create a query which only returns :
text
text2
text3
I tried something with instr() to get the index, but instr() was not recognized as a function -> SQL Error: no such function: instr (probably old version of db . sqlite_version()-> 3.7.5).
Any hints howto achieve this ?
There are two approaches:
You can rtrim the string of all characters other than the # character.
This assumes, of course, that (a) there is only one # in the string; and (b) that you're dealing with simple strings (e.g. 7-bit ASCII) in which it is easy to list all the characters to be stripped.
You can use sqlite3_create_function to create your own rendition of INSTR. The specifics here will vary a bit upon how you're using
Related
Since my texts are in Portuguese, there are many words with accent and other special characters, like: "coração", "hambúrguer", "São Paulo".
Normally, I treat these names in Python with the following function:
from unicodedata import normalize
def string_normalizer(text):
result = normalize("NFKD", text.lower()).encode("ASCII", "ignore").decode("ASCII")
return result.replace(" ", "-")
This would replace the blank spaces with '-', replace special characters and apply a lowercase convertion. The word "coração" would become "coracao", "São Paulo" would become "Sao Paulo" and so on. Now, I'm not sure what's the best way to do this in Redshift. My solution would be to apply multiple replaces, something like this:
replace(replace(replace(lower(column), 'á', 'a'), 'ç', 'c')...
Even though this works, it doesn't look like the best solution. Is there an easy way to normalize my string?
In Redshift, you can use the translate function to normalize a string. The translate function takes three arguments: the source string, the characters to replace, and the replacement characters. You can use this function to replace all the special characters in your string with their ASCII equivalent.
For example, the following query uses the translate function to replace all the special characters in a string with their ASCII equivalent. Additionally, spaces are replaced with "-" characters.
SELECT translate('São Paulo', ' áàãâäéèêëíìîïóòõôöúùûüçÁÀÃÄÉÈÊËÍÌÎÏÓÒÕÖÔÚÙÛÜÇ', '-aaaaaeeeeiiiiooooouuuucAAAAAEEEEIIIIOOOOOUUUUC')
This query would return the string "Sao Paulo". You can use the lower function to convert the string to lowercase.
Here's an example of how you could use these functions together to normalize a string:
SELECT lower(translate('São Paulo', ' áàãâäéèêëíìîïóòõôöúùûüçÁÀà ÄÉÈÊËÍÌÎÏÓÒÕÖÔÚÙÛÜÇ', '-aaaaaeeeeiiiiooooouuuucAAAAAEEEEIIIIOOOOOUUUUC'))
This query would return the string "sao-paulo".
I have two types of URL's which I would need to clean, they look like this:
["//xxx.com/se/something?SE_{ifmobile:MB}{ifnotmobile:DT}_A_B_C_D_E_F_G_H"]
["//www.xxx.com/se/car?p_color_car=White?SE_{ifmobile:MB}{ifnotmobile:DT}_A_B_C_D_E_F_G_H"]
The outcome I want is;
SE_{ifmobile:MB}{ifnotmobile:DT}_A_B_C_D_E_F_G_H"
I want to remove the brackets and everything up to SE, the URLS differ so I want to remove:
First URL
["//xxx.com/se/something?
Second URL:
["//www.xxx.com/se/car?p_color_car=White?
I can't get my head around it,I've tried this .*\/ . But it will still keep strings I don't want such as:
(1 url) =
something?
(2 url) car?p_color_car=White?
You can use
regexp_replace(FinalUrls, r'.*\?|"\]$', '')
See the regex demo
Details
.*\? - any zero or more chars other than line breakchars, as many as possible and then ? char
| - or
"\]$ - a "] substring at the end of the string.
Mind the regexp_replace syntax, you can't omit the replacement argument, see reference:
REGEXP_REPLACE(value, regexp, replacement)
Returns a STRING where all substrings of value that match regular
expression regexp are replaced with replacement.
You can use backslashed-escaped digits (\1 to \9) within the
replacement argument to insert text matching the corresponding
parenthesized group in the regexp pattern. Use \0 to refer to the
entire matching text.
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.
From within an Oracle 11g database, using SQL, I need to remove the following sequence of special characters from a string, i.e.
~!##$%^&*()_+=\{}[]:”;’<,>./?
If any of these characters exist within a string, except for these two characters, which I DO NOT want removed, i.e.: "|" and "-" then I would like them completely removed.
For example:
From: 'ABC(D E+FGH?/IJK LMN~OP' To: 'ABCD EFGHIJK LMNOP' after removal of special characters.
I have tried this small test which works for this sample, i.e:
select regexp_replace('abc+de)fg','\+|\)') from dual
but is there a better means of using my sequence of special characters above without doing this string pattern of '\+|\)' for every special character using Oracle SQL?
You can replace anything other than letters and space with empty string
[^a-zA-Z ]
here is online demo
As per below comments
I still need to keep the following two special characters within my string, i.e. "|" and "-".
Just exclude more
[^a-zA-Z|-]
Note: hyphen - should be in the starting or ending or escaped like \- because it has special meaning in the Character class to define a range.
For more info read about Character Classes or Character Sets
Consider using this regex replacement instead:
REGEXP_REPLACE('abc+de)fg', '[~!##$%^&*()_+=\\{}[\]:”;’<,>.\/?]', '')
The replacement will match any character from your list.
Here is a regex demo!
The regex to match your sequence of special characters is:
[]~!##$%^&*()_+=\{}[:”;’<,>./?]+
I feel you still missed to escape all regex-special characters.
To achieve that, go iteratively:
build a test-tring and start to build up your regex-string character by character to see if it removes what you expect to be removed.
If the latest character does not work you have to escape it.
That should do the trick.
SELECT TRANSLATE('~!##$%sdv^&*()_+=\dsv{}[]:”;’<,>dsvsdd./?', '~!##$%^&*()_+=\{}[]:”;’<,>./?',' ')
FROM dual;
result:
TRANSLATE
-------------
sdvdsvdsvsdd
SQL> select translate('abc+de#fg-hq!m', 'a+-#!', etc.) from dual;
TRANSLATE(
----------
abcdefghqm