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

Code Generator

Language

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r"(?m)(?P<query_date>\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}Z UTC) \[ db=(?P<db>\w+) LOG:(?P<query_text>[\w|\W]*?;)").unwrap(); let string = "'2021-06-23T08:02:08Z UTC [ db=dev LOG: BEGIN; '2021-06-23T08:02:08Z UTC [ db=dev LOG: SET datestyle TO ISO; '2021-06-23T08:02:08Z UTC [ db=dev LOG: SET TRANSACTION READ ONLY; '2021-06-23T08:02:08Z UTC [ db=dev LOG: SET STATEMENT_TIMEOUT TO 300000; '2021-06-23T08:02:08Z UTC [ LOG: /* hash: 8d9692aa66628f2ea5b0b9de8e4ea59b */ SELECT action, status, COUNT(*) AS num_req FROM stl_datashare_changes_consumer WHERE actiontime > getdate() - INTERVAL '1 day' GROUP BY 1,2; '2021-06-23T08:02:08Z UTC [ LOG: SELECT pg_catalog.stll_datashare_changes_consumer.action AS action, pg_catalog.stll_datashare_changes_consumer.status AS status, COUNT(*) AS num_req FROM pg_catalog.stll_datashare_changes_consumer WHERE pg_catalog.stll_datashare_changes_consumer.actiontime > getdate() - interval '1 day'::Interval GROUP BY 1, 2; '2021-06-23T08:02:08Z UTC [ LOG: COMMIT; '2021-06-23T08:02:08Z UTC [ LOG: SET query_group to '' '2021-06-23T08:02:22Z UTC [ LOG: SELECT 1 '2021-06-23T08:02:30Z UTC [ LOG: /* hash: 64f5dca78e917617f51632257854cb2f */ WITH per_commit_info AS ( SELECT date_trunc('day', startwork) AS day, c.xid, SUM(num_metadata_blocks_retained) AS sum_retained, SUM(total_metadata_blocks) AS sum_total, AVG(num_metadata_blocks_retained) AS avg_retained, AVG(total_metadata_blocks) AS avg_total FROM stl_commit_stats c, stl_commit_internal_stats i WHERE c.xid = i.xid < ...even more sql >; '2021-06-23T08:02:30Z UTC [ LOG: SELECT per_commit_info.day AS day, COUNT(*) AS commits, "; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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 Rust, please visit: https://docs.rs/regex/latest/regex/