# Split delimited text into rows

Shape / rows

A variant of [Split a list into rows](https://meridian.online/operations/split-a-list-into-rows).

Split a text value on a separator or pattern and emit one row per item.

Page: <https://meridian.online/operations/split-a-list-into-rows/split-delimited-text-into-rows>

## Status

Runs as a SQL step.

arcform carries it as a `sql:` step today.

## The DuckDB step

split delimited text on a separator or a pattern, one row per item

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
-- orders.tags is separated by '|'; an order with no tags has no items, so it emits no row
CREATE TEMP TABLE by_separator AS
SELECT order_id, unnest(string_split(tags, '|')) AS tag FROM orders;
-- a pattern: commas, semicolons or bars, each with any spaces around it
CREATE TEMP TABLE notes AS SELECT * FROM (VALUES (1, 'red, green;blue'), (2, 'one | two')) t(id, colours);
CREATE TEMP TABLE by_pattern AS
SELECT id, unnest(regexp_split_to_array(colours, '\s*[,;|]\s*')) AS colour FROM notes;
SELECT * FROM by_separator ORDER BY order_id, tag;
SELECT * FROM by_pattern ORDER BY id, colour;
SELECT CASE WHEN ((SELECT count(*) FROM by_separator) = 13 AND (SELECT list(tag ORDER BY tag) FROM by_separator WHERE order_id = 10) = ['a', 'b', 'c'] AND (SELECT count(DISTINCT order_id) FROM by_separator) = 8 AND (SELECT list(colour ORDER BY colour) FROM by_pattern WHERE id = 1) = ['blue', 'green', 'red'] AND (SELECT list(colour ORDER BY colour) FROM by_pattern WHERE id = 2) = ['one', 'two']) THEN 'as expected' ELSE error('the tags did not split into 13 rows over 8 orders, or the colours did not split into three and two trimmed items') END AS verdict;
```

It needs nothing installed beyond DuckDB itself.

## What other tools call it

Meridian's classification; an independent blind rating agreed on 95.7% of 324 rows (variant, version 3).

- Duckle: [`Normalize`](https://github.com/slothflowlabs/duckle/blob/f85f8960edfb6efbf4cb89d58a7b32e16df0e867/website/docs/components.html) (read 2026-09-25)
- EasyMorph: [`Split delimited text into rows`](https://help.easymorph.com/doku.php?id=transformations:subfield) (read 2026-09-27)
- Apache Hop: [`Split fields to rows`](https://hop.apache.org/manual/latest/pipeline/transforms/splitfieldtorows.html) (read 2026-09-27)
- OpenRefine: [`Split multi-valued cells…`](https://openrefine.org/docs/manual/cellediting#split-multi-valued-cells) (read 2026-09-27)
- Pentaho Data Integration: [`Split field to rows`](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview) (read 2026-09-27)
- Talend: [`tNormalize`](https://help.qlik.com/talend/en-US/components/8.0/processing/processing-component) (read 2026-09-27)
- Trifacta: [`Split into rows`](https://help.alteryx.com/aac/en/trifacta-classic/reference/transformation-reference.html) (read 2026-09-27)
- Trifacta: [`Splitrows Transform`](https://help.alteryx.com/aac/en/trifacta-classic/wrangle-language/language-appendices/transforms.html) (read 2026-09-27)