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): when an error occurs, instead of erroring out, suppress the error message

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