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EXPLODE_BITMAP

Description

The explode_bitmap table function accepts a bitmap type data and maps each bit in the bitmap to a separate row. It is commonly used to process bitmap data, expanding each element in the bitmap into a separate record. It should be used together with LATERAL VIEW. explode_bitmap_outer is similar to explode_bitmap, but behaves differently when handling empty or NULL values. It allows records with empty or NULL bitmaps to exist and expands them into NULL rows in the result.

Syntax

EXPLODE_BITMAP(<bitmap>)

Parameters

Return Value

  • Returns a row for each bit in <bitmap>, with each row containing a bit value.

Usage Notes

  1. If the <bitmap> parameter is not of type BITMAP, an error will be reported.

Examples

  1. Prepare data
    create table example(
    k1 int
    ) properties(
    "replication_num" = "1"
    );

    insert into example values(1);
  2. Regular parameters
    select k1, e1 from example lateral view explode_bitmap(bitmap_from_string("1,3,4,5,6,10")) t2 as e1 order by k1, e1;
    +------+------+
    | k1 | e1 |
    +------+------+
    | 1 | 1 |
    | 1 | 3 |
    | 1 | 4 |
    | 1 | 5 |
    | 1 | 6 |
    | 1 | 10 |
    +------+------+
  3. Empty BITMAP
    select k1, e1 from example lateral view explode_bitmap(bitmap_from_string("")) t2 as e1 order by k1, e1;
    Empty set (0.03 sec)
  4. NULL parameter
    select  * from example lateral view explode_bitmap(NULL) t2 as c;
    Empty set (0.03 sec)
  5. Non-array parameter
    select  * from example lateral view explode_bitmap('abc') t2 as c;
    ERROR 1105 (HY000): errCode = 2, detailMessage = Can not find the compatibility function signature: explode_bitmap(VARCHAR(3))