# Match with a regular expression Shape / columns regex extract, match, replace Page: ## Status Runs as a SQL step. arcform carries it as a `sql:` step today. ## The DuckDB step extract named groups It reads the `orders` table the proofs share. Create it first: ```sql CREATE TABLE orders AS SELECT * FROM (VALUES (1, 'Alice Ng', 'north', DATE '2026-01-03', 120.00, 'widget', 'a|b', '{"channel":"web","items":[1,2]}'), (2, 'alice ng', 'north', DATE '2026-01-05', 80.50, 'gadget', 'b', '{"channel":"shop","items":[3]}'), (3, 'Bob Okafor', 'south', DATE '2026-01-05', 300.00, 'widget', 'a|c', '{"channel":"web","items":[4,5,6]}'), (4, 'Carla Díaz', 'east', DATE '2026-01-09', NULL, 'gizmo', NULL, '{"channel":"web","items":[]}'), (5, 'Bob Okafor', 'south', DATE '2026-01-12', 45.25, 'gadget', 'c', '{"channel":"phone","items":[7]}'), (6, 'Dev Patel', 'west', DATE '2026-01-12', 510.00, 'widget', 'a', '{"channel":"web","items":[8,9]}'), (7, 'Carla Diaz', 'east', DATE '2026-01-20', 99.99, 'gizmo', 'b|c', '{"channel":"shop","items":[10]}'), (8, 'Dev Patel', 'west', DATE '2026-02-02', 510.00, 'widget', 'a', '{"channel":"web","items":[8,9]}'), (9, 'Eve Larsen', NULL, DATE '2026-02-03', 15.00, 'gadget', NULL, '{"channel":"web","items":[11]}'), (10, 'Alice Ng', 'north', DATE '2026-02-10', 220.00, 'gizmo', 'a|b|c', '{"channel":"phone","items":[12,13]}') ) t(order_id, customer, region, order_date, amount, product, tags, meta); ``` Then run the statement: ```sql CREATE TEMP TABLE result AS SELECT order_id, order_date::VARCHAR AS s, regexp_extract(order_date::VARCHAR, '(\d+)-(\d+)-(\d+)', ['y','m','d']) AS parts FROM orders; SELECT * FROM result; SELECT CASE WHEN ((SELECT max(parts.y) = '2026' AND max(parts.m) FILTER (WHERE order_id = 10) = '02' AND max(parts.d) FILTER (WHERE order_id = 10) = '10' FROM result)) THEN 'as expected' ELSE error('the date did not come apart into year, month and day') END AS verdict; ``` It needs nothing installed beyond DuckDB itself. ## Variants - [Extract with a regular expression](https://meridian.online/operations/match-with-a-regular-expression/extract-with-a-regular-expression): Copy the parts of a value that match a pattern, or its capture groups, into new columns or an array. - [Replace with a regular expression](https://meridian.online/operations/match-with-a-regular-expression/replace-with-a-regular-expression): Replace or remove the parts of a value that match a pattern, optionally using backreferences. - Test for a pattern match: Test whether, or count how often, a value matches a regular expression or LIKE pattern. ## What other tools call it Meridian's classification; an independent blind rating agreed on 86.2% of 312 rows (exact class, version 2). - Alteryx Designer: [`RegEx`](https://help.alteryx.com/current/en/designer/tools/parse/regex-tool.html) (read 2026-09-27) - Apache DataFusion: [`Regular Expression Functions`](https://datafusion.apache.org/user-guide/sql/scalar_functions.html) (read 2026-09-27) - DuckDB: [`Pattern Matching (family)`](https://duckdb.org/docs/current/sql/functions/pattern_matching) (read 2026-09-27) - DuckDB: [`Regular Expressions (family)`](https://duckdb.org/docs/current/sql/functions/regular_expressions) (read 2026-09-27) - Duckle: [`Regex Extract`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Regex Match`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - Duckle: [`Regex Replace`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25) - EasyMorph: [`Regular expression`](https://help.easymorph.com/doku.php?id=transformations:regexp) (read 2026-09-27) - AWS Glue: [`Extract string fragments from a regular expression`](https://docs.aws.amazon.com/glue/latest/dg/transforms-regex-extractor.html) (read 2026-09-27) - Apache Hop: [`Regex Evaluation`](https://hop.apache.org/manual/latest/pipeline/transforms/regexeval.html) (read 2026-09-27) - Ibis: [`RegexExtract`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/strings.py) (read 2026-09-27) - Ibis: [`RegexReplace`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/strings.py) (read 2026-09-27) - Ibis: [`RegexSearch`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/strings.py) (read 2026-09-27) - Ibis: [`RegexSplit`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/strings.py) (read 2026-09-27) - Ibis: [`StringSQLILike`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/strings.py) (read 2026-09-27) - Ibis: [`StringSQLLike`](https://github.com/ibis-project/ibis/blob/05d2b293344e86cb41c1a426071734f7e270335a/ibis/expr/operations/strings.py) (read 2026-09-27) - KNIME Analytics Platform: [`String Splitter (Regex)`](https://api.hub.knime.com/nodes/*KUuLa8QggcD_9C01?details=full) (read 2026-09-27) - Apache NiFi: [`ExtractGrok`](https://nifi.apache.org/components/org.apache.nifi.processors.standard.ExtractGrok/) (read 2026-09-27) - Apache NiFi: [`ExtractText`](https://nifi.apache.org/components/org.apache.nifi.processors.standard.ExtractText/) (read 2026-09-27) - Apache NiFi: [`ReplaceText`](https://nifi.apache.org/components/org.apache.nifi.processors.standard.ReplaceText/) (read 2026-09-27) - Apache NiFi: [`Searching`](https://nifi.apache.org/nifi-docs/expression-language-guide.html) (read 2026-09-27) - OpenRefine: [`Find and replace`](https://openrefine.org/docs/manual/grelfunctions#find-and-replace) (read 2026-09-27) - OpenRefine: [`Testing string characteristics`](https://openrefine.org/docs/manual/grelfunctions#testing-string-characteristics) (read 2026-09-27) - Pentaho Data Integration: [`Regex Evaluation`](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview) (read 2026-09-27) - Polars: [`Expr.str: pattern match, extract and replace (group)`](https://docs.pola.rs/api/python/stable/reference/expressions/string.html) (read 2026-09-27) - Polars: [`escape_regex`](https://docs.pola.rs/api/python/stable/reference/functions.html) (read 2026-09-27) - RapidMiner Studio: [`Keep Document Parts`](https://docs.rapidminer.com/latest/studio/operators/extensions/Text%20Processing/transformation/keep_document_parts.html) (read 2026-09-27) - RapidMiner Studio: [`Remove Document Parts`](https://docs.rapidminer.com/latest/studio/operators/extensions/Text%20Processing/transformation/remove_document_parts.html) (read 2026-09-27) - RapidMiner Studio: [`Replace`](https://docs.rapidminer.com/latest/studio/operators/blending/values/replace.html) (read 2026-09-27) - RapidMiner Studio: [`Replace (In Database)`](https://docs.rapidminer.com/latest/studio/operators/extensions/In-Database%20Processing/indb_blending/indb_replace.html) (read 2026-09-27) - RapidMiner Studio: [`Replace Tokens`](https://docs.rapidminer.com/latest/studio/operators/extensions/Text%20Processing/transformation/replace_tokens.html) (read 2026-09-27) - Apache SeaTunnel: [`RegexExtract`](https://seatunnel.apache.org/docs/2.3.13/transforms/regexextract) (read 2026-09-27) - Talend: [`tExtractRegexFields`](https://help.qlik.com/talend/en-US/components/8.0/data-extraction/data-extraction-component) (read 2026-09-27) - Talend: [`tPatternExtract`](https://help.qlik.com/talend/en-US/components/8.0/data-extraction/data-extraction-component) (read 2026-09-27) - Talend: [`tStandardizeRow`](https://help.qlik.com/talend/en-US/components/8.0/standardization/standardization-component) (read 2026-09-27) - Trifacta: [`Count matches`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`Count matches between delimiters`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`Countpattern Transform`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/language-appendices/transforms.html) (read 2026-09-27) - Trifacta: [`Extract Transform`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/language-appendices/transforms.html) (read 2026-09-27) - Trifacta: [`Extract between delimiters`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`Extract matches to Array`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`Extract numbers`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`Extract text or pattern`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27) - Trifacta: [`Extractlist Transform`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/language-appendices/transforms.html) (read 2026-09-27) - VisiData: [`addcol-capture`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/regex.py#L139) (read 2026-09-23) - VisiData: [`addcol-regex-subst`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/regex.py#L141) (read 2026-09-23) - VisiData: [`addcol-subst`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/deprecated.py#L232) (read 2026-09-23) - VisiData: [`capture-col`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/deprecated.py#L237) (read 2026-09-23) - VisiData: [`setcol-regex-subst`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/regex.py#L142) (read 2026-09-23) - VisiData: [`setcol-regex-subst-all`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/regex.py#L143) (read 2026-09-23) - VisiData: [`setcol-subst`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/deprecated.py#L233) (read 2026-09-23) - VisiData: [`setcol-subst-all`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/deprecated.py#L234) (read 2026-09-23)