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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"@Prompt\('[^']*'(\s*,\s*'[^']*')*\)") test_str = ("SELECT\n" " sum(EXT_BAD_DEBT_HIST.BILL_AMT),\n" " sum(EXT_BAD_DEBT_HIST.BILL_OPEN_AMT),\n" " TIME_MONTH.YEAR,\n" " TIME_MONTH.MONTH_NAME,\n" " @Prompt('Desired %','N',,Mono,free,Not_Persistent),\n" " TIME_MONTH.MONTH_NUM_OVERALL,\n" " TIME_MONTH.FIRST_DAY,\n" " TIME_MONTH.LAST_DAY\n" "FROM\n" " TIME_MONTH INNER JOIN EXT_BAD_DEBT_HIST ON (EXT_BAD_DEBT_HIST.MONTH_NUM_OVERALL=TIME_MONTH.MONTH_NUM_OVERALL)\n" " INNER JOIN RSK_SHARED.LO_PRICE_GROUP RSK_SHARED_LO_PRICE_GROUP2 ON (RSK_SHARED_LO_PRICE_GROUP2.PRICE_GROUP_KEY=EXT_BAD_DEBT_HIST.CUST_PGROUP)\n\n" "WHERE\n" " (\n" " TRUNC(EXT_BAD_DEBT_HIST.BD_DATE) = TRUNC(SYSDATE)\n" " AND\n" " EXT_BAD_DEBT_HIST.CUSTOMER_CATEGORY_CODE = 20\n" " AND\n" " ( EXT_BAD_DEBT_HIST.BILL_CYCLE = @Prompt('Bill Cycle','A','MIGRATION\\BC',Mono,primary_key,Not_Persistent) OR -1 = @Prompt('Bill Cycle','A','MIGRATION\\BC',Mono,primary_key,Not_Persistent) )\n" " AND\n" " TIME_MONTH.FIRST_DAY Is Not Null\n" " AND\n" " TIME_MONTH.LAST_DAY Is Not Null\n" " AND\n" " (\n" " ( RSK_SHARED_LO_PRICE_GROUP2.PRICE_GROUP In @Prompt('Price Groups Sub-Groups','A','[Lookup] Price Group (2)\\Nested Price Group',Multi,Constrained,Not_Persistent) OR ('All Large 552' In @Prompt('Price Groups Sub-Groups','A','[Lookup] Price Group (2)\\Nested Price Group',Multi,Constrained,Not_Persistent) AND RSK_SHARED_LO_PRICE_GROUP2.PRICE_GROUP_CODE = 4) OR ('All SME' In @Prompt('Price Groups Sub-Groups','A','[Lookup] Price Group (2)\\Nested Price Group',Multi,Constrained,Not_Persistent) AND RSK_SHARED_LO_PRICE_GROUP2.PRICE_GROUP_CODE = 5) OR 'All' In @Prompt('Price Groups Sub-Groups','A','[Lookup] Price Group (2)\\Nested Price Group',Multi,Constrained,Not_Persistent) )\n" " AND\n" " EXT_BAD_DEBT_HIST.CUST_PGROUP <> 154\n" " AND\n" " EXT_BAD_DEBT_HIST.CUST_PGROUP NOT BETWEEN 161 AND 166\n" " )\n" " )\n" "GROUP BY\n" " TIME_MONTH.YEAR,\n" " TIME_MONTH.MONTH_NAME,\n" " @Prompt('Desired %','N',,Mono,free,Not_Persistent),\n" " TIME_MONTH.MONTH_NUM_OVERALL,\n" " TIME_MONTH.FIRST_DAY,\n" " TIME_MONTH.LAST_DAY") 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