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"CREATE TABLE \[.*\) ON \[PRIMARY\]", flags=re.DOTALL) test_str = ("CREATE TABLE [Company](\n" " [CompanyName] [varchar](255) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [Address1] [varchar](255) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [Address2] [varchar](255) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [City] [varchar](255) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [State] [varchar](50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [Zip] [numeric](18, 0) NOT NULL\n" ") ON [PRIMARY]\n\n" "GO\n\n" "GO\n" "SET ANSI_PADDING ON\n\n" "GO\n" "CREATE NONCLUSTERED INDEX [IX_Company] ON [Company]\n" "(\n" " [CompanyName] ASC\n" ")WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 80) ON [PRIMARY]\n" "GO\n\n" "GO\n" "ALTER TABLE [Company] ADD CONSTRAINT [DF_Company_CompanyName] DEFAULT ('') FOR [CompanyName]\n" "GO\n" "ALTER TABLE [Company] ADD CONSTRAINT [DF_Company_Address1] DEFAULT ('') FOR [Address1]\n" "GO\n" "ALTER TABLE [Company] ADD CONSTRAINT [DF_Company_Address2] DEFAULT ('') FOR [Address2]\n" "GO\n" "ALTER TABLE [Company] ADD CONSTRAINT [DF_Company_City] DEFAULT ('') FOR [City]\n" "GO\n" "ALTER TABLE [Company] ADD CONSTRAINT [DF_Company_State] DEFAULT ('') FOR [State]\n" "GO\n" "ALTER TABLE [Company] ADD CONSTRAINT [DF_Company_Zip] DEFAULT ((0)) FOR [Zip]\n" "GO\n\n" "GO\n\n" "-- =============================================\n" "-- Counties TABLE\n" "-- =============================================\n" "SET ANSI_NULLS ON\n" "GO\n" "SET QUOTED_IDENTIFIER ON\n" "GO\n" "CREATE TABLE [Counties](\n" " [UID] [varchar](50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [CountyName] [varchar](50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [StateUID] [varchar](50) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,\n" " [SurTax] [money] NOT NULL\n" ") ON [PRIMARY]") 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