select for filters

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

Signature

> select ...rest --ignore-errors

Parameters

  • ...rest: the columns to select from the table
  • --ignore-errors (-i): ignore missing data (make all cell path members optional)

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.

Examples

Select a column in a table

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

Select a field in a record

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

Select just the name column

> ls | select name

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

> ls | select 0 1 2 3