Dear Monks

Although I'm using regular expressions for years, thinking that I could do almost everything with them, I realized today its not true.
The problem that I encountered had todo with a string that needs to be inserted into a MySQL database, for example:
$values = "'abc', 'dec'f', ''ghc''" ;
$sql = "INSERT INTO SOME_TABLE ($columns) VALUES($values) ;

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So I need todo something with this string that would result into:
'abc' 'dec\'f' '\'ghc\''

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Normally I would be happy if someone gave me the answer, but this time I would really like to understand the regular expression!
So I will show below what I tried!
The first 2 thing I did were:
$insert =~ s/(?<!^)'/\\'/g ; # gives: 'abc\' \'dec\'f\' \'...
# and I tried:
$insert =~ /s(?<!\s)'/\\'/g ; # gives \'abc\' 'dec\'f\'...

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Next step is to combine:
$insert =~ s/(?<!\s)'|(?<!^)'/\\'/g ; # wrong result :(
$insert =~ s/(?<![^\s]/\\'/g ; # nope again

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At this point I could really use some help on combining the 2 ?

Thans
LuCa

In reply to string manipulations with regular expressions by jeanluca

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