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"(.?(?:FROM)\ [a-zA-Z_]+(?:\.[a-zA-Z_]+)?)") test_str = ("SELECT sl.subscription_link_id link_data_id\n" " , sl.subscription_id link_sub_id\n" " , a.adoption_id link_id\n" " , a.date_created link_start_date\n" " , dispatches.bill_charge_id link_charge_id\n" " , dispatches.total_amount link_amount\n" " , dispatches.status link_charge_status\n" " , dispatches.date_created link_charge_date_created\n" " , dispatches.date_modified link_charge_date_modified\n" " , dispatches.bill_fin_instrument_id charge_bill_fin_instrument_id\n" " , dispatches.date_resolved charge_resolved\n" " , dispatches.lp_exp_date charge_lp_exp_date\n" " , a.date_modified link_date_modified\n" " , a.date_created link_date_created\n" " , dispatches.base_price_type_id link_base_price_type_id\n" " , dispatches.status link_bill_charge_status\n" " , CASE\n" " WHEN ls.exp_date IS NOT NULL\n" " THEN ls.exp_date\n" " ELSE add_months(l.date_created, lp.num1 * DECODE(lp.num2,1,12,2,1) )\n" " END link_end_date\n" " , CASE\n" " WHEN ls.exp_date IS NOT NULL\n" " THEN 1\n" " ELSE (lp.num1 * DECODE(lp.num2,1,12,2,1,5,0,0))\n" " END link_term\n" "FROM emetadata.ers_subscription_links sl\n" " , emetadata.ers_adoptions a\n" " , emetadata.ers_adopt_fulfillments af\n" " , emetadata.ers_licenses l\n" " , emetadata.ers_license_parameters lp\n" " , emetadata.ers_license_slots ls\n" " , (SELECT adopt_charge.bill_charge_id\n" " , adopt_charge.status\n" " ,adopt_charge.total_amount\n" " , partitions.date_resolved\n" " ,partitions.lp_exp_date\n" " , adopt_charge.adoption_id\n" " ,adopt_charge.date_created\n" " , adopt_charge.date_modified\n" " , adopt_charge.bill_fin_instrument_id\n" " , adopt_charge.base_price_type_id\n" " FROM\n" " (SELECT bc.bill_charge_id\n" " , bc.status\n" " , bc.date_created\n" " , bc.date_modified\n" " , bc.total_amount\n" " , bc.bill_fin_instrument_id\n" " , acl.adoption_id\n" " ,oicl.base_price_type_id\n" " FROM emetadata.ersmd_adoption_charge_link acl\n" " , emetadata.ers_bill_charge bc\n" " , emetadata.ers_order_charge_links oicl\n" " WHERE acl.charge_id = bc.bill_charge_id AND oicl.bill_charge_id = bc.bill_charge_id\n" " ) adopt_charge\n" " , (SELECT pcl.bill_charge_id\n" " , bd.date_resolved\n" " , cpi.lp_exp_date\n" " FROM emetadata.ers_bill_dispatches bd\n" " , emetadata.ers_charge_partitions cp\n" " , emetadata.ersmd_charge_partition_info cpi\n" " , emetadata.ers_part_charge_link pcl\n" " WHERE cp.charge_partition_id = bd.charge_partition_id (+) AND cp.charge_partition_id=cpi.charge_partition_id(+) AND cp.charge_partition_id =\n" " pcl.charge_partition_id AND cp.status = 3\n" " ) partitions\n" " WHERE adopt_charge.bill_charge_id = partitions.bill_charge_id (+)\n" " ) dispatches\n" "WHERE a.subscription_link_id = sl.subscription_link_id AND af.adoption_id = a.adoption_id AND a.adoption_id = dispatches.adoption_id (+) AND\n" " af.fulfillment_target_id = l.license_id AND l.license_id = lp.license_id AND l.license_id = ls.license_id (+);\n") 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