Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gi

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'select * from a where #myTable$@_¥£.$@_¥£#columnName like (\'%\'+@p2+\'%\') select * from a where #myTable$_¥£.$_¥£#columnName like (\'%\'+@p2+\'%\') (\\w|\\[|\\]|\\.|\\s|\'|\\+|\\(|\\)|\\,) select a from b where h like (\'%\'+@p2+\'%\') having b.d like (\'%\'+@p2) )join c on a.b like (@p2+\'%\') and a.b like (@p2) if a like (\'%abc24\'\'as\'+@p2+\'%\') case when a like (\'%\'+@p2+\'%\') where (((a like (\'%\'+ @p2+\'%\')))) where a + \'b\' like (\'%\'+@p2+\'%\') where concat(a,b) like (\'%\'+@p2+\'%\') or ltrim(a) like (\'%\'+@p2+\'%\') select * from a where concat(a,b) like \'a\' and c like d or ltrim(a) like (\'%\'+@p2+\'%\') where isnull(ltrim(a), \'0\') like (\'%\'+@p2+\'%\') where a + \'b\' LIKe (\'%\'+@p2+\'%\') vICM_EVENTlike roadshowev0like_ where upper(roadshowev0like_.EVENT_NAME) like (\'%\'+@p1+\'%\') or upper(roadshowev0like_.EVENT_SYMBOLlike) like (\'%\'+@p2+\'%\') and e_.EVENT_SYMBOLike like(\'%\'+@p2+\'%\') from vICM_INVESTOR investor0_ where (upper(investor0_.OrgId) like (\'%\'+@p1+\'%\') or upper(investor0_.Name) like (\'%\'+@p2+\'%\')) and investor0_.IsDeactivated=@p3 order by investor0_.Name asc where ((h.g) + upper(concat(investor0_.OrgId, \'d\') + (a.d)) like (\'%\'+@p1+\'%\') or upper(investor0_.Name) like (\'%\'+@p2+\'%\')) and investor0_.IsDeactivated=@p3 order by investor0_.Name asc where (a.b like (\'%\'+@p2+\'%\')) and d.g like (\'%\'+@p2+\'%\') (where a.b like (\'%\'+@p2) if a like (\'%\'+@p2) join a on b.d like (\'%\'+@p2) // not supported where a like \'b\' and c like (\'%\'+@p2+\'%\') where a like (\' \'+@p1+\'%\') // supported where a like (\'%\'+@p1+\'%\') and c like (\'%\'+@p2+\'%\') '; my $regex = qr/((?<=[ )()']where)|(?<=[ )()']and)|(?<=[ )()']o[rn])|(?<=[ )()']if)|(?<=[ )()']when)|(?<=having))+(\s|\()+[)(,'+_¥£$#\@\w\[\]\.\s]+like\s*\(?\s*(('((\w|%|'{2})*)')\s*\+)*\s*@p\d+\s*(\+('%'))*\)/ip; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html