BITMAP_EMPTY Function

bitmap_empty()

Description

The BITMAP_EMPTY function returns an empty bitmap.

Parameters

• No parameters.

Return Type

• Returns BITMAP type, representing an empty bitmap with no elements.

Examples

1. Create an empty bitmap

   SELECT bitmap_to_string(bitmap_empty());
   +----------------------------------+
   | bitmap_to_string(bitmap_empty()) |
   +----------------------------------+
   |                                  |
   +----------------------------------+
   

2. Count elements in an empty bitmap

   SELECT bitmap_cardinality(bitmap_empty());
   +-----------------------------------+
   | bitmap_cardinality(bitmap_empty())|
   +-----------------------------------+
   | 0                                 |
   +-----------------------------------+
   

3. Convert an empty bitmap to an array

   SELECT bitmap_to_array(bitmap_empty());
   +--------------------------------+
   | bitmap_to_array(bitmap_empty())|
   +--------------------------------+
   | []                             |
   +--------------------------------+