# Regular-expression input settings

The regexp input format matches one complete physical line and maps capture groups to destination columns. The captured field is then decoded with the chosen escaping rule.

A pattern is required because its default is empty. regexp_skip_unmatched can skip nonmatching lines; it does not remove target-type validation from matching captures.

Use a statement `SETTINGS` clause. Defaults in `system.settings` are read-only;
format settings cannot be persisted with `SET`. Put input settings before
`FORMAT`, because the bytes after the format name are input data.

## regexp_escaping

Type: `String`

Default value: `Raw`

Read captured fields as Raw text, Escaped text, Quoted literals, CSV fields, or JSON values.

Applies to: `regexp`.

## regexp_pattern

Type: `String`

Default value: `''`

Match every complete input line; one capture group supplies each target column. Empty requires a statement override.

Applies to: `regexp`.

## regexp_skip_unmatched

Type: `Bool`

Default value: `0`

Skip lines that do not match the expression; otherwise report their physical line number.

Applies to: `regexp`.