select for filters

Select only these columns or rows from the input. Opposite of `reject`.

Signature

> select {flags} ...rest

Flags

• --optional, -o: make all cell path members optional (returns null for missing values)
• --ignore-case: make all cell path members case insensitive
• --ignore-errors, -i: ignore missing data (make all cell path members optional) (deprecated)

Parameters

• ...rest: The columns to select from the table.

Input/output types:

Examples

Select a column in a table

> [{a: a b: b}] | select a
╭───┬───╮
│ # │ a │
├───┼───┤
│ 0 │ a │
╰───┴───╯

Select a column even if some rows are missing that column

> [{a: a0 b: b0} {b: b1}] | select -o a
╭───┬────╮
│ # │ a  │
├───┼────┤
│ 0 │ a0 │
│ 1 │    │
╰───┴────╯

Select a field in a record

> {a: a b: b} | select a
╭───┬───╮
│ a │ a │
╰───┴───╯

Select just the name column

Select the first four rows (this is the same as first 4)

Select multiple columns

> [[name type size]; [Cargo.toml toml 1kb] [Cargo.lock toml 2kb]] | select name type
╭───┬────────────┬──────╮
│ # │    name    │ type │
├───┼────────────┼──────┤
│ 0 │ Cargo.toml │ toml │
│ 1 │ Cargo.lock │ toml │
╰───┴────────────┴──────╯

Select multiple columns by spreading a list

> let cols = [name type]; [[name type size]; [Cargo.toml toml 1kb] [Cargo.lock toml 2kb]] | select ...$cols
╭───┬────────────┬──────╮
│ # │    name    │ type │
├───┼────────────┼──────┤
│ 0 │ Cargo.toml │ toml │
│ 1 │ Cargo.lock │ toml │
╰───┴────────────┴──────╯

Notes

This differs from get in that, rather than accessing the given value in the data structure, it removes all non-selected values from the structure. Hence, using select on a table will produce a table, a list will produce a list, and a record will produce a record.