Need guidance with Regular Expression in Python - python-3.x

I need help with one of my current tasks wherein i am trying to pick only the table names from the query via Python
So basically lets say a query looks like this
Create table a.dummy_table1
as
select a.dummycolumn1,a.dummycolumn2,a.dummycolumn3 from dual
Now i am passing this query into Python using STRINGIO and then reading only the strings where it starts with "a" and has "_" in it like below
table_list = set(re.findall(r'\ba\.\w+', str(data)))
Here data is the dataframe in which i have parsed the query using StringIO
now in table_list i am getting the below output
a.dummy_table1
a.dummycolumn1
a.dummycolumn2
whereas the Expected output should have been like
a.dummy_table1
<Let me know how we can get this done , have tried the above regular expression but that is not working properly>
Any help on same would be highly appreciated


Your current regex string r"\ba.\w+" simply matches any string which:
Begins with "a" (the "\ba" part)
Followed by a period (the "." part)
Followed by 1 or more alphanumeric characters (the "\w+" part).
If I've understood your problem correctly, you are looking to extract from str(data) any string fragments which match this pattern instead:
Begins with "a"
Followed by a period
Followed by 1 or more alphanumeric characters
Followed by an underscore
Followed by 1 or more alphanumeric characters
Thus, the regular expression should have "_\w+" added to the end to match criteria 4 and 5:
table_list = set(re.findall(r"\ba\.\w+_\w+", str(data)))

Related

how to modify textfile using U-SQL

I have a large file of around 130MB containing 10 A characters in each line and \t at the end of 10th "A" character, I want to extract this text file and then change all A's to B's. Can any one help with its code snippet?
this is what I have wrote till now
USE DATABASE imodelanalytics;
#searchlog =
EXTRACT characters string
FROM "/iModelAnalytics/Samples/Data/dummy.txt"
USING Extractors.Text(delimiter: '\t', skipFirstNRows: 1);
#modify =
SELECT characters AS line
FROM #searchlog;
OUTPUT #modify
TO "/iModelAnalytics/Samples/Data/B.txt"
USING Outputters.Text();
I'm new to this, so any suggestions will be helpful ! Thanks

Assuming all of the field would be AAAAAAAAAA then you could write:
#modify = SELECT "BBBBBBBBBB" AS characters FROM #searchlog;
If only some are all As, then you would do it in the SELECT clause:
#modify =
SELECT (characters == "AAAAAAAAAA" ? "BBBBBBBBBB" : characters) AS characters
FROM #searchlog;
If there are other characters around the AAAAAAAAAA then you would use more of the C# string functions to find them and replace them in a similar pattern.

Find index of a specific character in a string then parse the string

I have strings which looks like this [NAME LASTNAME/NAME.LAST#emailaddress/123456678]. What I want to do is parse strings which have the same format as shown above so I only get NAME LASTNAME. My psuedo idea is find the index of the first instance of /, then strip from index 1 to that index of / we found. I want this as a VBScript.

Your way should work. You can also Split() your string on / and just grab the first element of the resulting array:
Const SOME_STRING = "John Doe/John.Doe#example.com/12345678"
WScript.Echo Split(SOME_STRING, "/")(0)
Output:
John Doe
Edit, with respect to comments.
If your string contains the [, you can still Split(). Just use Mid() to grab the first element starting at character position 2:
Const SOME_STRING = "[John Doe/John.Doe#example.com/12345678]"
WScript.Echo Mid(Split(SOME_STRING, "/")(0), 2)

Your idea is good here, you should also need to grab index for "[".This will make script robust and flexible here.Below code will always return strings placed between first occurrence of "[" and "/".
var = "[John Doe/John.Doe#example.com/12345678]"
WScript.Echo Mid(var, (InStr(var,"[")+1),InStr(var,"/")-InStr(var,"[")-1)

Display the specific part of the string in PostgreSQL 9.3

I have a string to modify as per the requirements.
For example:
The given string is:
str1 varchar = '123,456,789';
I want to show the string as:
'456,789'
Note: The first part (delimited) with comma, I want to remove from string and show the rest of string.
In SQL Server I used STUFF() function.
SELECT STUFF('123,456,789',1,4,'');
Result:
456,789
Question: Is there any string function in PostgreSQL 9.3 version to do the same job?

you can use regular expressions:
select substring('123,456,789' from ',(.*)$');
The comma matches the first comma found in the string. The part inside the brackets (.*) is returned from the function. The symbol $ means the end of the string.
A alternative solution without regular expressions:
select str, substring(str from position(',' in str)+1 for length(str)) from
(select '123,456,789'::text as str) as foo;

You could first turn the string to array and return second and third cell:
select array_to_string((regexp_split_to_array('123,456,789', ','))[2:3], ',')
Or you could use substring-function with regular expressions (pattern matching):
SELECT substring('123,456,789' from '[0-9]+,([0-9]+,[0-9]+)')
[0-9]+ means one or more digits
parentheses tell to return that part from the string
Both solutions work on your specific string.

Your The SQL Server example indicates you just want to remove the first 4 characters, which makes the rest of your question seem misleading because it completely ignores what's in the string. Only the positions matters.
Be that as it may, the simple and cheap way to cut off leading characters is with right():
SELECT right('123,456,789', -4);
SQL Fiddle.

rstrip() has no effect on string

Trying to use rstrip() at its most basic level, but it does not seem to have any effect at all.
For example:
string1='text&moretext'
string2=string1.rstrip('&')
print(string2)
Desired Result:
text
Actual Result:
text&moretext
Using Python 3, PyScripter
What am I missing?

someString.rstrip(c) removes all occurences of c at the end of the string. Thus, for example
'text&&&&'.rstrip('&') = 'text'
Perhaps you want
'&'.join(string1.split('&')[:-1])
This splits the string on the delimiter "&" into a list of strings, removes the last one, and joins them again, using the delimiter "&". Thus, for example
'&'.join('Hello&World'.split('&')[:-1]) = 'Hello'
'&'.join('Hello&Python&World'.split('&')[:-1]) = 'Hello&Python'

Lua: Search a specific string

Hi all tried all the string pattrens and library arguments but still stuck.
i want to get the name of the director from the following string i have tried the string.matcH but it matches the from the first character it finD from the string
the string is...
fixstrdirector = {id:39254,cast:[{id:15250,name:Hope Davis,character:Aunt Debra,order:5,cast_id:10,profile_path:/aIHF11Ss8P0A8JUfiWf8OHPVhOs.jpg},{id:53650,name:Anthony Mackie,character:Finn,order:3,cast_id:11,profile_path:/5VGGJ0Co8SC94iiedWb2o3C36T.jpg},{id:19034,name:Evangeline Lilly,character:Bailey Tallet,order:2,cast_id:12,profile_path:/oAOpJKgKEdW49jXrjvUcPcEQJb3.jpg},{id:6968,name:Hugh Jackman,character:Charlie Kenton,order:0,cast_id:13,profile_path:/wnl7esRbP3paALKn4bCr0k8qaFu.jpg},{id:79072,name:Kevin Durand,character:Ricky,order:4,cast_id:14,profile_path:/c95tTUjx5T0D0ROqTcINojpH6nB.jpg},{id:234479,name:Dakota Goyo,character:Max Kenton,order:1,cast_id:15,profile_path:/7PU6n4fhDuFwuwcYVyRNVEZE7ct.jpg},{id:8986,name:James Rebhorn,character:Marvin,order:6,cast_id:16,profile_path:/ezETMv0YM0Rg6YhKpu4vHuIY37D.jpg},{id:930729,name:Marco Ruggeri,character:Cliff,order:7,cast_id:17,profile_path:/1Ox63ukTd2yfOf1LVJOMXwmeQjO.jpg},{id:19860,name:Karl Yune,character:Tak Mashido,order:8,cast_id:18,profile_path:/qK315vPObCNdywdRN66971FtFez.jpg},{id:111206,name:Olga Fonda,character:Farra Lemkova,order:9,cast_id:19,profile_path:/j1qabOHf3Pf82f1lFpUmdF5XvSp.jpg},{id:53176,name:John Gatins,character:Kingpin,order:10,cast_id:41,profile_path:/A2MqnSKVzOuBf8MVfNyve2h2LxJ.jpg},{id:1126350,name:Sophie Levy,character:Big Sister,order:11,cast_id:42,profile_path:null},{id:1126351,name:Tess Levy,character:Little Sister,order:12,cast_id:43,profile_path:null},{id:1126352,name:Charlie Levy,character:Littlest Sister,order:13,cast_id:44,profile_path:null},{id:187983,name:Gregory Sims,character:Bill Panner,order:14,cast_id:45,profile_path:null}],crew:[{id:58726,name:Leslie Bohem,department:Writing,job:Screenplay,profile_path:null},{id:53176,name:John Gatins,department:Writing,job:Screenplay,profile_path:/A2MqnSKVzOuBf8MVfNyve2h2LxJ.jpg},{id:17825,name:Shawn Levy,department:Directing,job:Director,profile_path:/7f2f8EXdlWsPYN0HPGcIlG21xU.jpg},{id:12415,name:Richard Matheson,department:Writing,job:Story,profile_path:null},{id:57113,name:Dan Gilroy,department:Writing,job:Story,profile_path:null},{id:25210,name:Jeremy Leven,department:Writing,job:Story,profile_path:null},{id:17825,name:Shawn Levy,department:Production,job:Producer,profile_path:/7f2f8EXdlWsPYN0HPGcIlG21xU.jpg},{id:34970,name:Susan Montford,department:Production,job:Producer,profile_path:/1XJt51Y9ciPhkHrAYE0j6Jsmgji.jpg},{id:3183,name:Don Murphy,department:Production,job:Producer,profile_path:null},{id:34967,name:Rick Benattar,department:Production,job:Producer,profile_path:null},{id:1126348,name:Eric Hedayat,department:Production,job:Producer,profile_path:null},{id:186721,name:Ron Ames,department:Production,job:Producer,profile_path:null},{id:10956,name:Josh McLaglen,department:Production,job:Executive Producer,profile_path:null},{id:57634,name:Mary McLaglen,department:Production,job:Executive Producer,profile_path:null},{id:23779,name:Jack Rapke,department:Production,job:Executive Producer,profile_path:null},{id:488,name:Steven Spielberg,department:Production,job:Executive Producer,profile_path:/cuIYdFbEe89PHpoiOS9tmo84ED2.jpg},{id:30,name:Steve Starkey,department:Production,job:Executive Producer,profile_path:null},{id:24,name:Robert Zemeckis,department:Production,job:Executive Producer,profile_path:/isCuZ9PWIOyXzdf3ihodXzjIumL.jpg},{id:531,name:Danny Elfman,department:Sound,job:Original Music Composer,profile_path:/pWacZpYPos8io22nEiim7d3wp2j.jpg},{id:18265,name:Mauro Fiore,department:Crew,job:Cinematography,profile_path:null},{id:54271,name:Dean Zimmerman,department:Editing,job:Editor,profile_path:null},{id:25365,name:Richard Hicks,department:Production,job:Casting,profile_path:null},{id:5490,name:David Rubin,department:Production,job:Casting,profile_path:null},{id:52088,name:Tom Meyer,department:Art,job:Production Design,profile_path:null}]}
i have tried string.match(fixstrdirector,"name:(.+),department:Directing")
but it gives me the from the first occurace it find the name to the end of thr string
output:
Hope Davis,character:Aunt Debra,order:5,cast_id:10,profile_path:/aIHF11Ss8P0A8JUfiWf8OHPVhOs.jpg},{id:53650,name:Anthony Mackie,character:Finn,order:3,cast_id:11,profile_path:/5VGGJ0Co8SC94iiedWb2o3C36T.jpg},{id:19034,name:Evangeline Lilly,character:Bailey Tallet,order:2,cast_id:12,profile_path:/oAOpJKgKEdW49jXrjvUcPcEQJb3.jpg},{id:6968,name:Hugh Jackman,character:Charlie Kenton,order:0,cast_id:13,profile_path:/wnl7esRbP3paALKn4bCr0k8qaFu.jpg},{id:79072,name:Kevin Durand,character:Ricky,order:4,cast_id:14,profile_path:/c95tTUjx5T0D0ROqTcINojpH6nB.jpg},{id:234479,name:Dakota Goyo,character:Max Kenton,order:1,cast_id:15,profile_path:/7PU6n4fhDuFwuwcYVyRNVEZE7ct.jpg},{id:8986,name:James Rebhorn,character:Marvin,order:6,cast_id:16,profile_path:/ezETMv0YM0Rg6YhKpu4vHuIY37D.jpg},{id:930729,name:Marco Ruggeri,character:Cliff,order:7,cast_id:17,profile_path:/1Ox63ukTd2yfOf1LVJOMXwmeQjO.jpg},{id:19860,name:Karl Yune,character:Tak Mashido,order:8,cast_id:18,profile_path:/qK315vPObCNdywdRN66971FtFez.jpg},{id:111206,name:Olga Fonda,character:Farra Lemkova,order:9,cast_id:19,profile_path:/j1qabOHf3Pf82f1lFpUmdF5XvSp.jpg},{id:53176,name:John Gatins,character:Kingpin,order:10,cast_id:41,profile_path:/A2MqnSKVzOuBf8MVfNyve2h2LxJ.jpg},{id:1126350,name:Sophie Levy,character:Big Sister,order:11,cast_id:42,profile_path:null},{id:1126351,name:Tess Levy,character:Little Sister,order:12,cast_id:43,profile_path:null},{id:1126352,name:Charlie Levy,character:Littlest Sister,order:13,cast_id:44,profile_path:null},{id:187983,name:Gregory Sims,character:Bill Panner,order:14,cast_id:45,profile_path:null}],crew:[{id:58726,name:Leslie Bohem,department:Writing,job:Screenplay,profile_path:null},{id:53176,name:John Gatins,department:Writing,job:Screenplay,profile_path:/A2MqnSKVzOuBf8MVfNyve2h2LxJ.jpg},{id:17825,name:Shawn Levy

You're searching from the first occurrence of "name:" until the "department:Directing" with everything in between.
Instead, you need to restrict what can be between the two strings. Here for example I'm saying that the characters that make up the name can only be alphanumeric or a space:
string.match(fixstrdirector,"name:([%w ]+),department:Directing")
Alternatively, given that there's a comma separating the parameters, a better approach would be to search for "name:" followed by any characters other than a comma, followed by "department:Directing":
string.match(fixstrdirector,"name:([^,]+),department:Directing")
Of course that wouldn't work if the name had a comma it in!

Lua patterns provides - modifier for tasks as you have above. As stated on PiL - Section 20.2:
The + modifier matches one or more characters of the original class.
It will always get the longest sequence that matches the pattern.
Like *, the modifier - also matches zero or more occurrences of
characters of the original class. However, instead of matching the
longest sequence, it matches the shortest one.
Next, when you are using . to match, it'll find any and all characters satisfying the pattern. Therefore, you'll get the result from first occurence of name until the ,department:Directing is found. Since you know that it is a JSON data, you can try to match for [^,]; that is, non-comma characters.
So, for your case try:
local tAllNames = {}
for sName in fixstrdirector:gmatch( "name:([^,]-),department:Directing" ) do
tAllNames[ #tAllNames + 1 ] = sName
end
and all your required names will be stored in the table tAllNames. An example of the above can be seen at codepad.

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