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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(aS)\s+((\`)?\w+(\`)?)(\s+|\,|(FRom\s+))", flags=re.MULTILINE | re.IGNORECASE) 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 = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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