ruby regex not working to remove class name from sql - ruby

I have:
BEFORE Gsub sql ::::
SELECT record_type.* FROM record_type WHERE (name = 'Registrars')
sql = sql.gsub(/SELECT\s+[^\(][A-Z]+\./mi,"SELECT ")
AFTER GSUB SQL ::::
SELECT record_type.* FROM record_type WHERE (name = 'Registrars')
The desired result is to remove the "record_type." from the statement:
So it should be :
SELECT * FROM record_type WHERE (name = 'Registrars')
After the regex is run.
I didn't write this, it's in the asf-soap-adaptor gem. Can someone tell me why it doesn't work, and how to fix?

I suppose it should be written like this...
sql = sql.gsub(/SELECT\s+[^\(][A-Z_]+\./mi,"SELECT ")
... as the code in the question won't match if the field name contains _ (underscore) symbol. I suppose that's why this code is in gem: it can work in some conditions (i.e., with underscoreless field names).
Still, I admit I don't understand why exactly this replacement should be done - and shouldn't it include 0-9 check as well (as, for example, 'record_id1' field still won't be matched - and replaced - by the character class in the regular expression; you may have to either expand it, like [0-9A-Z_], or just replace completely with \w).

so your before and after gsubs are the same? I can't tell you why it doesn't work if you dont tell me your expected result. Also for help with interpreting ruby regular expressions check out rubular.com

Related

How can I use 'update where' select in FoxPro?

I am totally new to FoxPro (and quite fluent with MySQL).
I am trying to execute this query in FoxPro:
update expertcorr_memoinv.dbf set 'Memo' = (select 'Memo' from expertcorr_memoinv.dbf WHERE Keymemo='10045223') WHERE Keydoc like "UBOA"
I got the error:
function name is missing )
How can I fix it?
In FoxPro SQL statements you would not 'single-quote' column names. In Visual FoxPro version 9 the following sequence would run without errors:
CREATE TABLE expertcorr_memoinv (keydoc Char(20), keymemo M, Memo M)
Update expertcorr_memoinv.dbf set Memo = (select Memo from expertcorr_memoinv.dbf WHERE Keymemo='10045223') WHERE Keydoc like "UBOA"
If you would provide a few sample data and an expected result, we could see whether the line you posted would do what you want after correcting the single-quoted 'Memo' names.
NB 1: "Memo" is a reserved word in FoxPro.
NB 2: As you know, the ";" semicolon is a line-continuation in Visual FoxPro, so that a longer SQL statement can be full; of; those;
So that the Update one-liner could be written as:
Update expertcorr_memoinv ;
Set Memo = (Select Memo From expertcorr_memoinv ;
WHERE Keymemo='10045223') ;
WHERE Keydoc Like "UBOA"
NB 3: Alternatively, you can SQL Update .... From... in Visual FoxPro, similar to the Microsoft SQL Server feature. See How do I UPDATE from a SELECT in SQL Server?
I would do that just as Stefan showed.
In VFP, you also have a chance to use non-SQL statements which make it easier to express yourself. From your code it feels like KeyMemo is a unique field:
* Get the Memo value into an array
* where KeyMemo = '10045223'
* or use that as a variable also
local lcKey
lcKey = '10045223'
Select Memo From expertcorr_memoinv ;
WHERE Keymemo=m.lcKey ;
into array laMemo
* Update with that value
Update expertcorr_memoinv ;
Set Memo = laMemo[1] ;
WHERE Keydoc Like "UBOA"
This is only for divide & conquer strategy that one may find easier to follow. Other than that writing it with a single SQL is just fine.
PS: In VFP you don't use backticks at all.
Single quotes, double quotes and opening closing square brackets are not used as identifiers but all those three are used for string literals.
'This is a string literal'
"This is a string literal"
[This is a string literal]
"My name is John O'hara"
'We need 3.5" disk'
[Put 3.5" disk into John's computer]
There are subtle differences between them, which I think is an advanced topic and that you may never need to know.
Also [] is used for array indexer.
Any one of them could also be used for things like table name, alias name, file name ... (name expression) - still they are string literals, parentheses make it a name expression. ie:
select * from ('MyTable') ...
copy to ("c:\my folder\my file.txt") type delimited

Regular Expression to match both first characters and last character in oracle

I have a table with a column with the structure:
Table name : re_result
res_id
--------------
PSI8765450
PSIRRRRTY781
ABCD000001
I want to fetch the values starting with PSI and ending with 1. My expected output is PSIRRRRTY781.
I am using query
Select * from re_result
Where regexp_like(^PSI*1)
But I am not getting the output. I am getting both PSIRRRRTY781 and ABCD000001.
Plz help
You do not need regular expressions; a simpler LIKE may do the work:
select res_id
from re_result
where res_id like 'PSI%1'
The same thing can be done with regexp:
where regexp_like(res_id, '^PSI(.*)1$')
This matches 'PSI' in the beginning of the string and '1' as last character, just before the end of string ($).
Here you find something more on regexp in Oracle
Another way to handle your query.
SELECT res_id FROM re_result WHERE UPPER(res_id) like UPPER('PSI%1')

Oracle regex for all characters after a specific character

I need to get all characters after the last 'R' from a part number like this:
223A GHH R337716
So far I've got:
REGEXP_SUBSTR(CUST_PART_NO,'R(.*)')
This returns R337716, but I don't want the 'R' and I'm not sure if it would work if there was more than one 'R' in the string.
Then you have to replace the string with groups of expressions like this:
regexp_replace( CUST_PART_NO, '(.*)(R)(.*)', '\3' )
See it here on sqlfiddle: http://sqlfiddle.com/#!4/3ec77/2
What I'm saying with this expression is:
get everything until R make it as a group 1 expression the first (.*)
get the R make it the second group (R)
get everything else and make it the third group (.*)
The parenthesis on a regular expression define groups of expressions.
What about
ltrim(REGEXP_SUBSTR(CUST_PART_NO,'R(.*)'), 'R')

Whats the XPath equivalent to SQL In query?

I would like to know whats the XPath equivalent to SQL In query. Basically in sql i can do this:
select * from tbl1 where Id in (1,2,3,4)
so i want something similar in XPath/Xsl:
i.e.
//*[#id= IN('51417','1121','111')]
Please advice
(In XPath 2,) the = operator always works like in.
I.e. you can use
//*[#id = ('51417','1121','111')]
A solution is to write out the options as separate conditions:
//*[(#id = '51417') or (#id = '1121') or (#id = '111')]
Another, slightly less verbose solution that looks a bit like a hack, though, would be to use the contains function:
//*[contains('-51417-1121-111-', concat('-', #id, '-'))]
Literally, this means you're checking whether the value of the id attribute (preceeded and succeeded by a delimiter character) is a substring of -51417-1121-111-. Note that I am using a hyphen (-) as a delimiter of the allowable values; you can replace that with any character that will not appear in the id attribute.

Ruby MatchData class is repeating captures, instead of including additional captures as it "should"

Ruby 1.9.1, OSX 10.5.8
I'm trying to write a simple app that parses through of bunch of java based html template files to replace a period (.) with an underscore if it's contained within a specific tag. I use ruby all the time for these types of utility apps, and thought it would be no problem to whip up something using ruby's regex support. So, I create a Regexp.new... object, open a file, read it in line by line, then match each line against the pattern, if I get a match, I create a new string using replaceString = currentMatch.gsub(/./, '_'), then create another replacement as whole string by newReplaceRegex = Regexp.escape(currentMatch) and finally replace back into the current line with line.gsub(newReplaceRegex, replaceString) Code below, of course, but first...
The problem I'm having is that when accessing the indexes within the returned MatchData object, I'm getting the first result twice, and it's missing the second sub string it should otherwise be finding. More strange, is that when testing this same pattern and same test text using rubular.com, it works as expected. See results here
My pattern:
(<(?:WEBOBJECT|webobject) (?:NAME|name)=(?:[a-zA-Z0-9]+.)+(?:[a-zA-Z0-9]+)(?:>))
Text text:
<WEBOBJECT NAME=admin.normalMode.someOtherPatternWeDontWant.moreThatWeDontWant>moreNonMatchingText<WEBOBJECT NAME=admin.SecondLineMatch>AndEvenMoreNonMatchingText
Here's the relevant code:
tagRegex = Regexp.new('(<(?:WEBOBJECT|webobject) (?:NAME|name)=(?:[a-zA-Z0-9]+\.)+(?:[a-zA-Z0-9]+)(?:>))+')
testFile = File.open('RegexTestingCompFix.txt', "r+")
lineCount=0
testFile.each{|htmlLine|
lineCount += 1
puts ("Current line: #{htmlLine} at line num: #{lineCount}")
tagMatch = tagRegex.match(htmlLine)
if(tagMatch)
matchesArray = tagMatch.to_a
firstMatch = matchesArray[0]
secondMatch = matchesArray[1]
puts "First match: #{firstMatch} and second match #{secondMatch}"
tagMatch.captures.each {|lineMatchCapture|
puts "Current capture for tagMatches: #{lineMatchCapture} of total match count #{matchesArray.size}"
#create a new regex using the match results; make sure to use auto escape method
originalPatternString = Regexp.escape(lineMatchCapture)
replacementRegex = Regexp.new(originalPatternString)
#replace any periods with underscores in a copy of lineMatchCapture
periodToUnderscoreCorrection = lineMatchCapture.gsub(/\./, '_')
#replace original match with underscore replaced copy within line
htmlLine.gsub!(replacementRegex, periodToUnderscoreCorrection)
puts "The modified htmlLine is now: #{htmlLine}"
}
end
}
I would think that I should get the first tag in matchData[0] then the second tag in matchData1, or, what I'm really doing because I don't know how many matches I'll get within any given line is matchData.to_a.each. And in this case, matchData has two captures, but they're both the first tag match
which is: <WEBOBJECT NAME=admin.normalMode.someOtherPatternWeDontWant.moreThatWeDontWant>
So, what the heck am I doing wrong, why does rubular test give me the expected results?
You want to use the on String#scan instead of the Regexp#match:
tag_regex = /<(?:WEBOBJECT|webobject) (?:NAME|name)=(?:[a-zA-Z0-9]+\.)+(?:[a-zA-Z0-9]+)(?:>)/
lines = "<WEBOBJECT NAME=admin.normalMode.someOtherPatternWeDontWant.moreThatWeDontWant>moreNonMatchingText\
<WEBOBJECT NAME=admin.SecondLineMatch>AndEvenMoreNonMatchingText"
lines.scan(tag_regex)
# => ["<WEBOBJECT NAME=admin.normalMode.someOtherPatternWeDontWant.moreThatWeDontWant>", "<WEBOBJECT NAME=admin.SecondLineMatch>"]
A few recommendations for next ruby questions:
newlines and spaces are your friends, you don't loose points for using more lines on your code ;-)
use do-end on blocks instead of {}, improves readability a lot
declare variables in snake case (hello_world) instead of camel case (helloWorld)
Hope this helps
I ended up using the String.scan approach, the only tricky point there was figuring out that this returns an array of arrays, not a MatchData object, so there was some initial confusion on my part, mostly due to my ruby green-ness, but it's working as expected now. Also, I trimmed the regex per Trevoke's suggestion. But snake case? Never...;-) Anyway, here goes:
tagRegex = /(<(?:webobject) (?:name)=(?:\w+\.)+(?:\w+)(?:>))/i
testFile = File.open('RegexTestingCompFix.txt', "r+")
lineCount=0
testFile.each do |htmlLine|
lineCount += 1
puts ("Current line: #{htmlLine} at line num: #{lineCount}")
oldMatches = htmlLine.scan(tagRegex) #oldMatches thusly named due to not explicitly using Regexp or MatchData, as in "the old way..."
if(oldMatches.size > 0)
oldMatches.each_index do |index|
arrayMatch = oldMatches[index]
aMatch = arrayMatch[0]
#create a new regex using the match results; make sure to use auto escape method
replacementRegex = Regexp.new(Regexp.escape(aMatch))
#replace any periods with underscores in a copy of lineMatchCapture
periodToUnderscoreCorrection = aMatch.gsub(/\./, '_')
#replace original match with underscore replaced copy within line, matching against the new escaped literal regex
htmlLine.gsub!(replacementRegex, periodToUnderscoreCorrection)
puts "The modified htmlLine is now: #{htmlLine}"
end # I kind of still prefer the brackets...;-)
end
end
Now, why does MatchData work the way it does? It seems like it's behavior is a bug really, and certainly not very useful in general if you can't get it provide a simple means of accessing all the matches. Just my $.02
Small bits:
This regexp helps you get "normalMode" .. But not "secondLineMatch":
<webobject name=\w+\.((?:\w+)).+> (with option 'i', for "case insensitive")
This regexp helps you get "secondLineMatch" ... But not "normalMode":
<webobject name=\w+\.((?:\w+))> (with option 'i', for "case insensitive").
I'm not really good at regexpt but I'll keep toiling at it.. :)
And I don't know if this helps you at all, but here's a way to get both:
<webobject name=admin.(\w+) (with option 'i').

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