This CL make bitmap_count, bitmap_union, and bitmap_union_count accept any expression whose return type is bitmap as input so that we can support flexible bitmap expression such as bitmap_count(bitmap_and(to_bitmap(1), to_bitmap(2))). This CL also create separate documentation for each bitmap UDF to conform with other functions.
1.3 KiB
1.3 KiB
bitmap_empty
description
Syntax
BITMAP BITMAP_EMPTY()
返回一个空bitmap。主要用于 insert 或 stream load 时填充默认值。例如
cat data | curl --location-trusted -u user:passwd -T - -H "columns: dt,page,v1,v2=bitmap_empty()" http://host:8410/api/test/testDb/_stream_load
example
mysql> select bitmap_count(bitmap_empty());
+------------------------------+
| bitmap_count(bitmap_empty()) |
+------------------------------+
| 0 |
+------------------------------+
keyword
BITMAP_EMPTY,BITMAP