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

const regex = /^(?=\s*SELECT\s+([\s\S]*?)(?=\s+(?:INTO|FROM|WHERE|GROUP\s+BY|HAVING|ORDER\s+BY)\s))(?=(?:[\s\S]*?\s+INTO\s+([\S]+)\s*)?)(?=(?:[\s\S]*?\s+FROM\s+([\s\S]*?)(?=\s+(?:WHERE|GROUP\s+BY|HAVING|ORDER\s+BY)\s)))(?=(?:[\s\S]*?\s+WHERE\s+([\s\S]*?)(?=\s+(?:GROUP\s+BY|HAVING|ORDER\s+BY)\s)))(?=(?:[\s\S]*?\s+GROUP\s+BY\s+([\s\S]*?)(?=\s+(?:HAVING|ORDER\s+BY)\s))?)(?=(?:[\s\S]*?\s+HAVING\s+([\s\S]*?)(?=\s+ORDER\s+BY\s))?)(?=(?:[\s\S]*?\s+ORDER\s+BY\s+([\s\S]*?)(?=\s*$))).*$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?=\\s*SELECT\\s+([\\s\\S]*?)(?=\\s+(?:INTO|FROM|WHERE|GROUP\\s+BY|HAVING|ORDER\\s+BY)\\s))(?=(?:[\\s\\S]*?\\s+INTO\\s+([\\S]+)\\s*)?)(?=(?:[\\s\\S]*?\\s+FROM\\s+([\\s\\S]*?)(?=\\s+(?:WHERE|GROUP\\s+BY|HAVING|ORDER\\s+BY)\\s)))(?=(?:[\\s\\S]*?\\s+WHERE\\s+([\\s\\S]*?)(?=\\s+(?:GROUP\\s+BY|HAVING|ORDER\\s+BY)\\s)))(?=(?:[\\s\\S]*?\\s+GROUP\\s+BY\\s+([\\s\\S]*?)(?=\\s+(?:HAVING|ORDER\\s+BY)\\s))?)(?=(?:[\\s\\S]*?\\s+HAVING\\s+([\\s\\S]*?)(?=\\s+ORDER\\s+BY\\s))?)(?=(?:[\\s\\S]*?\\s+ORDER\\s+BY\\s+([\\s\\S]*?)(?=\\s*$))).*$', 'gm') const str = `SELECT t1.dummy1, t1.dummy2, t1.dummy3 INTO testResult FROM (test1 t1 INNER JOIN test2 t2 ON t1.dummy4 = t2.dummy4) INNER JOIN test3 t3 ON t2.dummy9 = t3.dummy9 WHERE t2.dummy6 = 'abc' AND t3.dummy10 <> 'def' AND t1.dummy11 = 'ghi' AND t2.dummy12 IS NULL HAVING 1=1 ORDER BY 1;`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions