`uniq-by` for filters

Return the distinct values in the input by the given column(s).

Signature

> uniq-by {flags} ...rest

Flags

--count, -c: Return a table containing the distinct input values together with their counts.
--keep-last, -l: Return the last occurrence of each unique value instead of the first.
--repeated, -d: Return the input values that occur more than once.
--ignore-case, -i: Ignore differences in case when comparing input values.
--unique, -u: Return the input values that occur once only.

Parameters

...rest: The column(s) to filter by.

Input/output types:

input	output
table	table
list<any>	list<any>

Examples

Get rows from table filtered by column uniqueness.

> [[fruit count]; [apple 9] [apple 2] [pear 3] [orange 7]] | uniq-by fruit
╭───┬────────┬───────╮
│ # │ fruit  │ count │
├───┼────────┼───────┤
│ 0 │ apple  │     9 │
│ 1 │ pear   │     3 │
│ 2 │ orange │     7 │
╰───┴────────┴───────╯

Get rows from table filtered by column uniqueness, keeping the last occurrence of each duplicate.

> [[fruit count]; [apple 9] [apple 2] [pear 3] [orange 7]] | uniq-by fruit --keep-last
╭───┬────────┬───────╮
│ # │ fruit  │ count │
├───┼────────┼───────┤
│ 0 │ apple  │     2 │
│ 1 │ pear   │     3 │
│ 2 │ orange │     7 │
╰───┴────────┴───────╯