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

/
/
g

Test String

Code Generator

Language

Generated Code

$re = '/(_id`|\.`id`)\s*(!?=\s*\d+|IN\s*\([\d\,\s]*\))|FOR UPDATE|`ancestry`\s*(=|LIKE)\s*\'.*\'/'; $str = 'SELECT `ca_test`.`ex_journal_events`.* FROM `ca_test`.`ex_journal_events` WHERE `ca_test`.`ex_journal_events`.`office_id` = 36 AND `ca_test`.`ex_journal_events`.`office_member_id` = 6 LIMIT 1 FOR UPDATE WHERE `ca_production`.`office_member_depts`.`office_member_id` IN (6, 7) SELECT `ca_test`.`ex_journal_events`.* FROM `ca_test`.`ex_journal_events` WHERE `ca_test`.`ex_journal_events`.`office_member`.`id` = 6 SELECT `ca_test`.`ex_journal_events`.* FROM `ca_test`.`ex_journal_events` WHERE `ca_test`.`ex_journal_events`.`office`.`id` = SELECT `ca_production`.`permission`.* FROM `ca_production`.`permission` WHERE `ca_production`.`permission`.`office_member_id` IN (6, 8) SELECT `ca_production`.`permission`.* FROM `ca_production`.`permission` WHERE `ca_production`.`permission`.`office_id` IN (6, 8) SELECT `ca_production`.`permission`.* FROM `ca_production`.`permission` WHERE `ca_production`.`permission`.`office_member_id`=6 FOR UPDATE SELECT `ca_test`.`ex_journal_events`.* FROM `ca_test`.`ex_journal_events` WHERE `ca_test`.`ex_journal_events`.`office_member`.`user_id`=6 SELECT `ca_production`.`ex_items`.* FROM `ca_production`.`ex_items` WHERE `ca_production`.`ex_items`.`id` IN (5, 4) SELECT `ca_production`.`ex_items`.* FROM `ca_production`.`ex_items` WHERE `ca_production`.`ex_items`.`id` = 5 `permission`.`function_id` IN (6501, 6502, 6503) (pid:72013) (0.6ms) SELECT DISTINCT `ca_production`.`office_member`.`office_id` FROM `ca_production`.`office_member` INNER JOIN `ca_production`.`permission` ON `ca_production`.`permission`.`office_member_id` = `ca_production`.`office_member`.`id` WHERE `ca_production`.`office_member`.`deleted_at` IS NULL AND `ca_production`.`office_member`.`user_id` = 43 AND `permission`.`function_id` IN (6501, 6502, 6503) (pid:72013) SELECT `ca_production`.`project_codes`.* FROM `ca_production`.`project_codes` WHERE (`ca_production`.`project_codes`.`ancestry` LIKE \'283653/%\' OR `ca_production`.`project_codes`.`ancestry` = \'283653\')'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php