groupBitmapAnd

引入版本：v20.1.0 计算 bitmap 列的与运算，并返回其基数。如果添加后缀组合器 -State，则返回一个 bitmap 对象。语法

groupBitmapAnd(expr)
groupBitmapAndState(expr)

参数

expr — 结果类型为 AggregateFunction(groupBitmap, UInt*) 的表达式。AggregateFunction(groupBitmap, UInt*)

返回值 返回 UInt64 类型的计数值；使用 -State 时，则返回 bitmap 对象。UInt64 示例 用法示例

Query

CREATE TABLE bitmap_column_expr_test2
(
    tag_id String,
    z AggregateFunction(groupBitmap, UInt32)
)
ENGINE = MergeTree
ORDER BY tag_id;

INSERT INTO bitmap_column_expr_test2 VALUES ('tag1', bitmapBuild(cast([1,2,3,4,5,6,7,8,9,10] AS Array(UInt32))));
INSERT INTO bitmap_column_expr_test2 VALUES ('tag2', bitmapBuild(cast([6,7,8,9,10,11,12,13,14,15] AS Array(UInt32))));
INSERT INTO bitmap_column_expr_test2 VALUES ('tag3', bitmapBuild(cast([2,4,6,8,10,12] AS Array(UInt32))));

SELECT groupBitmapAnd(z) FROM bitmap_column_expr_test2 WHERE like(tag_id, 'tag%');

Response

┌─groupBitmapAnd(z)─┐
│               3   │
└───────────────────┘

使用 -State 组合器

Query

SELECT arraySort(bitmapToArray(groupBitmapAndState(z))) FROM bitmap_column_expr_test2 WHERE like(tag_id, 'tag%');

Response

┌─arraySort(bitmapToArray(groupBitmapAndState(z)))─┐
│ [6,8,10]                                         │
└──────────────────────────────────────────────────┘

​groupBitmapAnd

groupBitmapAnd