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

/
/
gm

Test String

Substitution

Processing...

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"Executed\s+as\s+user:\s+[\w\\]+\.|\[SQLSTATE \d+\] \(\w+ \d+\)\s*\.?" test_str = "Executed as user: Company\\SA_SQLA. Warning: Null value is eliminated by an aggregate or other SET operation. [SQLSTATE 01003] (Message 8153) Warning: Null value is eliminated by an aggregate or other SET operation. [SQLSTATE 01003] (Message 8153) Warning: Null value is eliminated by an aggregate or other SET operation. [SQLSTATE 01003] (Message 8153) Warning: Null value is eliminated by an aggregate or other SET operation. [SQLSTATE 01003] (Message 8153) The OLE DB provider \"MSOLEDBSQL\" for linked server \"linked_server\" does not contain the table \"\"databasename\".\"dbo\".\"table\"\". The table either does not exist or the current user does not have permissions on that table. [SQLSTATE 42000] (Error 7314) 2023-04-04 08:19:05.797: Fetching data, please wait... [SQLSTATE 01000] (Error 50000) 2023-04-04 08:19:05.797: Fetching data for Mar 4 2023 8:19AM, please wait... [SQLSTATE 01000] (Error 50000) 2023-04-04 08:20:07.813: Fetching data done! Starting Calculation, please wait... [SQLSTATE 01000] (Error 50000) 2023-04-04 08:20:22.657: Calculation Done! forwarding data, please wait... [SQLSTATE 01000] (Error 50000). The step failed." subst = "$0\\n" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # 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