Answer by exussum for Why non-greedy quantifier sometimes doesn't work in...
because your selecting too much SELECT regexp_substr( 'A=1,B=2,C=3,', '.*?B=.*?,' ) as A_and_B, -- Now works as expected regexp_substr( 'A=1,B=2,C=3,', 'B=.*?,' ) as B_only -- works just fine FROM dual...
View ArticleAnswer by Andrew Wolfe for Why non-greedy quantifier sometimes doesn't work...
You've got a really great bounty, so I'm going to try to nail it comprehensively. You make assumptions in your regular expression handling that are incorrect. Oracle is NOT compatible with Perl regular...
View ArticleAnswer by tbone for Why non-greedy quantifier sometimes doesn't work in...
Looking at the feedback, I hesitate to jump in, but here I go ;-) According to the Oracle docs, the *? and +? match a "preceding subexpression". For *? specifically: Matches zero or more occurrences of...
View ArticleAnswer by Old Pro for Why non-greedy quantifier sometimes doesn't work in...
It's a BUG! You are right that in Perl, 'A=1,B=2,C=3,' =~ /.*B=.*?,/; print $& prints A=1,B=2, What you have stumbled upon is a bug that still exists in Oracle Database 11g R2. If the exact same...
View ArticleWhy non-greedy quantifier sometimes doesn't work in Oracle regex?
IMO, this query should return A=1,B=2, SELECT regexp_substr('A=1,B=2,C=3,', '.*B=.*?,') as A_and_B FROM dual But it returns whole string A=1,B=2,C=3, instead. Why? UPD: Oracle 10.2+ required to use...
View ArticleAnswer by exussum for Why doesn't a non-greedy quantifier sometimes work in...
Because you're selecting too much:SELECT regexp_substr('A=1,B=2,C=3,','.*?B=.*?,' ) as A_and_B, -- Now works as expected regexp_substr('A=1,B=2,C=3,','B=.*?,' ) as B_only -- works just fineFROM dualSQL...
View ArticleAnswer by Andrew Wolfe for Why doesn't a non-greedy quantifier sometimes work...
You've got a really great bounty, so I'm going to try to nail it comprehensively.You make assumptions in your regular expression handling that are incorrect.Oracle is NOT compatible with Perl regular...
View ArticleAnswer by tbone for Why doesn't a non-greedy quantifier sometimes work in...
Looking at the feedback, I hesitate to jump in, but here I go ;-)According to the Oracle docs, the *? and +? match a "preceding subexpression". For *? specifically:Matches zero or more occurrences of...
View ArticleAnswer by Old Pro for Why doesn't a non-greedy quantifier sometimes work in...
It's a BUG!You are right that in Perl, 'A=1,B=2,C=3,' =~ /.*B=.*?,/; print $& prints A=1,B=2,What you have stumbled upon is a bug that still exists in Oracle Database 11g R2. If the exact same...
View ArticleWhy doesn't a non-greedy quantifier sometimes work in Oracle regex?
IMO, this query should return A=1,B=2,SELECT regexp_substr('A=1,B=2,C=3,', '.*B=.*?,') as A_and_B FROM dualBut it returns the whole string, A=1,B=2,C=3,, instead. Why?Update 1:Oracle 10.2+ is required...
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