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

r"
"
sg

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"CREATE\s+TABLE[^.]*\.(\S*)\s*\((.*?)PRIMARY KEY \(?\(([^)]*)\)\)?\s*\)\s*(?:WITH CLUSTERING ORDER BY \(([^)]*)\))?" test_str = ("CREATE TABLE abcdeg.table_v1 (\n" " \"id\" text,\n" " \"obj\" text,\n" " \"version\" bigint,\n" " output text,\n" " server text,\n" " PRIMARY KEY (\"id\", \"obj\", \"version\")\n" ") WITH CLUSTERING ORDER BY (\"id\" ASC, \"version\" DESC)\n" " AND bloom_filter_fp_chance = 0.1\n" " AND comment = ''\n" " AND default_time_to_live = 0\n" " AND gc_grace_seconds = 864000\n" " AND max_index_interval = 2048\n" " AND min_index_interval = 128\n" " AND read_repair_chance = 0.0\n" " AND speculative_retry = '99.0PERCENTILE';\n\n" "CREATE TABLE abcdeg.result_v1 (\n" " \"id\" text,\n" " \"obj\" text,\n" " time int,\n" " PRIMARY KEY ((\"id\", \"obj\"))\n" ") WITH bloom_filter_fp_chance = 0.1\n" " AND comment = ''\n" " AND default_time_to_live = 0\n" " AND gc_grace_seconds = 864000\n" " AND max_index_interval = 2048\n" " AND speculative_retry = '99.0PERCENTILE';") matches = re.finditer(regex, test_str, re.DOTALL) 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