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

/
/
xs

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r""" (?si) ^ \s* UPDATE \s+ `mytable` \s+ SET \s+ `keyname` \s* = \s* 'keyvalue' (?# one or more such key = value ) (?> \s* , \s* (?# field name ) ` [A-Z_]+ ` (?# equals ) \s* = \s* (?# value ) (?> (?# an integer, possibly negative ) -? [0-9]+ | (?# or, a string ) ' [^'\\]* (?: (?: \\ . | '' ) [^'\\]* )* ' # ' # (?: [^'\\] | '' | \\ . )* # ' | (?# or, literal NULL ) NULL ) )+ \s+ WHERE \s+ `keyname` \s* = \s* 'keyvalue' $ """ test_str = ("UPDATE `mytable`\n" "SET `keyname` = 'keyvalue',\n" "`Markup` =\n" "'Lorem ipsum dolor sit amet, consectetur adipiscing elit.\n" "''Quisque vel mattis odio, quis iaculis sem.''\n" "Nulla facilisi.\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\\r\\n\n" "\\'Aenean in augue a est vulputate accumsan.\\'\n" "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" "faucibus iaculis mi sed pulvinar.\\r\\n\n" "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\\r\\n\n" "\\'Aenean in augue a est vulputate accumsan.\\'\n" "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" "faucibus iaculis mi sed pulvinar.\\r\\n\n" "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\\r\\n\n" "\\'Aenean in augue a est vulputate accumsan.\\'\n" "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" "faucibus iaculis mi sed pulvinar.\\r\\n\n" "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\\r\\n\n" "\\'Aenean in augue a est vulputate accumsan.\\'\n" "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" "faucibus iaculis mi sed pulvinar.\\r\\n\n" "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\\r\\n\n" "\\'Aenean in augue a est vulputate accumsan.\\'\n" "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" "faucibus iaculis mi sed pulvinar.\\r\\n\n" "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" "faucibus enim tortor eget massa.Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\n" "Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere\n" "cubilia Curae; Fusce ut dui venenatis, maximus lorem eget, ornare ex.\n" "Aenean tempus pulvinar est, id fringilla enim sagittis id. Mauris finibus\n" "cursus commodo.\\r\\n\\r\\n\\r\\n\n" "\\'Aenean in augue a est vulputate accumsan.\\'\n" "Phasellus nulla diam, laoreet a elit non, mattis finibus magna. Phasellus\n" "faucibus iaculis mi sed pulvinar.\\r\\n\n" "Aliquam non nisl ultricies, aliquam augue vitae, efficitur sapien.\n" "Etiam viverra, magna a laoreet sollicitudin, ipsum erat tincidunt sem, nec\n" "faucibus enim tortor eget massa.\n" "Nunc nisi orci, lacinia vitae dictum et, vestibulum sed metus. ',\n" "`From_Date` = NULL,\n" "`To_Date` = NULL,\n" "`Foo` = '',\n" "`Box_Colour` = NULL,\n" "`Modification_Date` = '2016-09-08 12:30:47',\n" "`Modified_User` = 1,\n" "`Modified_IP` = '192.168.1.1'\n" "WHERE `keyname` = 'keyvalue'") matches = re.search(regex, test_str, re.VERBOSE | re.DOTALL) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html