bitmap_hash

Calculates a 32-bit hash value for any type of input and return the bitmap containing the hash value. It is mainly used for the stream load task to import non integer fields into the bitmap field of the StarRocks table. For example:

bash

cat data | curl --location-trusted -u user:passwd -T - \
    -H "columns: dt,page,device_id, device_id=bitmap_hash(device_id)" \
    http://host:8410/api/test/testDb/_stream_load

Syntax

Haskell

BITMAP BITMAP_HASH(expr)

Examples

Plain

MySQL > select bitmap_count(bitmap_hash('hello'));
+------------------------------------+
| bitmap_count(bitmap_hash('hello')) |
+------------------------------------+
|                                  1 |
+------------------------------------+

select bitmap_to_string(bitmap_hash('hello'));
+----------------------------------------+
| bitmap_to_string(bitmap_hash('hello')) |
+----------------------------------------+
| 1321743225                             |
+----------------------------------------+

keyword

BITMAP_HASH,BITMAP