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

/
/
igU

Test String

Code Generator

Language

Generated Code

$re = '/(?<prm>\w+)\s+.*:\s*=\s*\'(?<tbl>\w+)\'\s*;(?:.|\n)*(?:alter|create)\s+table\s+\'\s*\|\|\s*(\k<prm>\s+)/iU'; $str = 'DECLARE COUNTER NUMBER(10) := 0; pTABLENAME VARCHAR2(100) := \'ALM_AL1\'; pCOLUMNNAME VARCHAR2(100) := \'FLOATACCRUALDCBASISDAYC\'; pDATATYPE VARCHAR2(100) := \'NVARCHAR2(50) NULL\'; pSQL VARCHAR2(32000) := \' ALTER TABLE \' || pTABLENAME || \' ADD \' || pCOLUMNNAME || \' \' || pDATATYPE; BEGIN SELECT COUNT(0) INTO COUNTER FROM USER_TAB_COLUMNS WHERE TABLE_NAME=UPPER(pTABLENAME) AND COLUMN_NAME=UPPER(pCOLUMNNAME); IF COUNTER>0 THEN dbms_output.put_line(pTABLENAME || \' tablosunda \' || pCOLUMNNAME || \' kolonu var.\'); ELSE EXECUTE IMMEDIATE pSQL; dbms_output.put_line(pTABLENAME || \' tablosuna\' || pCOLUMNNAME || \' kolonu oluÅ?turuldu.\'); END IF; EXCEPTION WHEN OTHERS THEN dbms_output.put_line(\'HATA: \' || pSQL || \' -> SQLERRM: \' || SQLERRM); END; / DECLARE COUNTER NUMBER(10) := 0; pTABLENAME VARCHAR2(100) := \'ALM_AL2\'; pCOLUMNNAME VARCHAR2(100) := \'RATETYPETYPE\'; pDATATYPE VARCHAR2(100) := \'NVARCHAR2(40) NULL\'; pSQL VARCHAR2(32000) := \' ALTER TABLE \' || pTABLENAME || \' ADD \' || pCOLUMNNAME || \' \' || pDATATYPE; BEGIN SELECT COUNT(0) INTO COUNTER FROM USER_TAB_COLUMNS WHERE TABLE_NAME=UPPER(pTABLENAME) AND COLUMN_NAME=UPPER(pCOLUMNNAME); IF COUNTER>0 THEN dbms_output.put_line(pTABLENAME || \' tablosunda \' || pCOLUMNNAME || \' kolonu var.\'); ELSE EXECUTE IMMEDIATE pSQL; dbms_output.put_line(pTABLENAME || \' tablosuna\' || pCOLUMNNAME || \' kolonu oluÅ?turuldu.\'); END IF; EXCEPTION WHEN OTHERS THEN dbms_output.put_line(\'HATA: \' || pSQL || \' -> SQLERRM: \' || SQLERRM); END; / DECLARE COUNTER NUMBER(10) := 0; pTABLENAME VARCHAR2(100) := \'ALM_AL3\'; pCOLUMNNAME VARCHAR2(100) := \'PAYCURRENCYUNIT\'; pDATATYPE VARCHAR2(100) := \'NVARCHAR2(3) NULL\'; pSQL VARCHAR2(32000) := \' ALTER TABLE \' || pTABLENAME || \' ADD \' || pCOLUMNNAME || \' \' || pDATATYPE; BEGIN SELECT COUNT(0) INTO COUNTER FROM USER_TAB_COLUMNS WHERE TABLE_NAME=UPPER(pTABLENAME) AND COLUMN_NAME=UPPER(pCOLUMNNAME); IF COUNTER>0 THEN dbms_output.put_line(pTABLENAME || \' tablosunda \' || pCOLUMNNAME || \' kolonu var.\'); ELSE EXECUTE IMMEDIATE pSQL; dbms_output.put_line(pTABLENAME || \' tablosuna\' || pCOLUMNNAME || \' kolonu oluÅ?turuldu.\'); END IF; EXCEPTION WHEN OTHERS THEN dbms_output.put_line(\'HATA: \' || pSQL || \' -> SQLERRM: \' || SQLERRM); END; /'; 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