nullsfirst¶
Description¶
Specify the ordering as nulls first when processing data.
This is used by ordered windowing functions (like lag and last), ordered aggregation functions (like array_agg) and the sort verb.
Return type¶
ordering
Domain¶
This is a scalar function (calculates a single output value for a single input row.)
Categories¶
Usage¶
nullsfirst(value)
Argument |
Type |
Optional |
Repeatable |
Restrictions |
|---|---|---|---|---|
value |
storable or ordering |
no |
no |
none |
Examples¶
sort nullsfirst(foo)
Sort the dataset with nulls first in column foo.
statsby list:array_agg(username, asc(nullsfirst(timestamp))), group_by(hostname)
Lists all users for each host, in order of ascending timestamp with nulls first within each
host assuming you have a table with columns timestamp, hostname and username.