nullslast¶
Description¶
Specify the ordering as nulls last 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¶
nullslast( columnname )
Argument |
Type |
Required |
Multiple |
Constant |
---|---|---|---|---|
columnname |
ordering |
Required |
Only one |
Variable |
Examples¶
sort nullslast(desc(foo))
Sort the dataset in with nulls appearing last in descending order by values in column foo
.
statsby list:array_agg(username, nullslast(timestamp)), group_by(hostname)
Lists all users for each host, in order of ascending timestamp (default ordering) with nulls appearing last within each host assuming you have a table with columns timestamp
, hostname
and username
.