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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"
gmi

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"(aS)\s+((\`)?\w+(\`)?)(\s+|\,|(FRom\s+))" test_str = (" SELECT \n" " a.WORKORDER_NO AS workOrderNo, \n" " a.ORD_TYPE AS ordType, \n" " a.ORD_NO AS ordNo, \n" " a.RETURN_FLAG AS returnFlag, \n" " a.AREA_ID AS areaId, \n" " a.USER_NAME AS userName, \n" " a.ADDR_DETAIL AS addrDetail, \n" " a.HANDLE_STAFF_ID AS handleStaffId, \n" " a.TAKE_STAFF_ID AS takeStaffId, \n" " a.TAKE_TS AS takeTs, \n" " a.RETURN_STAFF_ID AS returnStaffId, \n" " a.RETURN_TS AS returnTs, \n" " a.SUMMARY AS summary, \n" " a.WO_TITLE AS woTitle, \n" " a.INSTALL_FLAG AS installFlag, \n" " a.START_TS AS startTs, \n" " a.END_TS AS endTs, \n" " a.GRID_ID AS gridId, \n" " a.SCHEMA_ID AS schemaId, \n" " a.PROJECT_ID AS projectId, \n" " a.COMMENTS AS comments, \n" " a.STATE AS `state`, \n" " a.CREATE_USER AS createUser, \n" " a.CREATE_DATE AS createDate, \n" " a.MODIFY_USER AS modifyUser, \n" " a.MODIFY_DATE AS modifyDate, \n" " a.HANDLE_TEAM_ID AS handleTeamId, \n" " a.PACKAGE_ID AS packageId, \n" " a.PACKAGE_NAME AS packageName, \n" " a.SUB_TYPE AS subType, \n" " a.pre_work_order_no AS preWorkOrderNo, \n" " a.IS_SYNC AS isSync, \n" " a.IS_VIRTUAL AS isVirtual, \n" " a.VIRTUAL_WORKORDER_NO AS virtualWorkOrderNo, \n" " a.VIRTUAL_WORKORDER_RES_ID AS virtualWorkOrderResId, \n" " a.IS_POLE AS isPole, \n" " a.VER_NO AS verNo, \n" " a.TASK_ID AS taskId, \n" " \n" " b.USER_NAME AS userName \n" " \n" " FROM oss_edn.edn_work_order a \n" " LEFT JOIN oss_wfm.wfs_user_infor b ON a.HANDLE_STAFF_ID = b.USER_ID \n" " WHERE a.WORKORDER_NO = :workOrderNo") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) 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