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

/
/
gm

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?P<timestamp>[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{6}Z) ? ? ? ? ? ?(?P<connID>[0-9]+) (?P<name>[a-zA-Z]+) (?P<sqltext>[^\n]+)" test_str = ("---my SQL--- \n\n" "2018-03-31T15:38:44.521650Z      2356 Query SELECT c FROM sbtest1 WHERE id=164802\n" "2018-03-31T15:38:44.521790Z      2356 Query SELECT c FROM sbtest1 WHERE id BETWEEN 95241 AND 95340\n" "2018-03-31T15:38:44.522168Z      2356 Query SELECT SUM(k) FROM sbtest1 WHERE id BETWEEN 1 AND 100\n" "2018-03-31T15:38:44.522500Z      2356 Query SELECT c FROM sbtest1 WHERE id BETWEEN 304556 AND 304655 ORDER BY c\n" "2018-03-31T15:38:44.522941Z      2356 Query SELECT DISTINCT c FROM sbtest1 WHERE id BETWEEN 924 AND 1023 ORDER BY c\n" "2018-03-31T15:38:44.523525Z      2356 Query UPDATE sbtest1 SET k=k+1 WHERE id=514") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.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