Help Center/ GaussDB(DWS)/ SQL Syntax Reference/ SQL Syntax Reference (8.3.0.x)/ Functions and Operators/ Bitmap Functions and Operators/ Roaring Bitmap Operators
Updated on 2024-09-03 GMT+08:00
View PDF
Share

Roaring Bitmap Operators

Since 8.1.3, GaussDB(DWS) supports efficient bitmap processing functions and operators, which can be used in user profiling and precision marketing, greatly improving query performance.

=

Description: Compares two Roaring bitmaps to check whether they are equal.

Return type: bool

Example:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
 
SELECT rb_build('{1,2,3}') = rb_build('{1,2,3}');
?column?
----------
t
(1 row)
SELECT rb_build('{2,3}') = rb_build('{1,2,3}');
?column?
----------
f
(1 row)

<>

Description: Compares two Roaring bitmaps to check whether they are unequal.

Return type: bool

Example:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
 
SELECT rb_build('{1,2,3}') <> rb_build('{1,2,3}');
?column?
----------
f
(1 row)
SELECT rb_build('{2,3}') <> rb_build('{1,2,3}');
?column?
----------
t
(1 row)

&

Description: Calculates the intersection of two Roaring bitmaps.

Return type: RoaringBitmap

Example:

1
2
3
4
5
 
SELECT rb_to_array(rb_build('{2,3}') & rb_build('{1,2,3}'));
rb_to_array
-------------
{2,3}
(1 row)

|

Description: Calculates the union of two Roaring bitmaps.

Return type: RoaringBitmap

Example:

1
2
3
4
5
 
SELECT rb_to_array(rb_build('{2,3}') | rb_build('{1,2,3}'));
rb_to_array
-------------
{1,2,3}
(1 row)

|

Description: Calculates the result of adding an ID to a Roaring bitmap.

Return type: RoaringBitmap

Example:

1
2
3
4
5
 
SELECT rb_to_array(rb_build('{2,3}') | 4);
rb_to_array
-------------
{2,3,4}
(1 row)

#

Description: XOR result of two Roaring bitmaps.

Return type: RoaringBitmap

Example:

1
2
3
4
5
 
SELECT rb_to_array(rb_build('{2,3}') # rb_build('{1,2,3}'));
rb_to_array
-------------
{1}
(1 row)

-

Description: Calculates the result set in the first Roaring bitmap but not in the second Roaring bitmap.

Return type: RoaringBitmap

Example:

1
2
3
4
5
 
SELECT rb_to_array(rb_build('{2,3,4}') - rb_build('{1,2,3}'));
rb_to_array
-------------
{4}
(1 row)

-

Description: The result set of removing a specified ID from a Roaring bitmap.

Return type: RoaringBitmap

Example:

1
2
3
4
5
 
SELECT rb_to_array(rb_build('{2,3,4}') - 3);
rb_to_array
-------------
{2,4}
(1 row)

@>

Description: Determines whether the Roaring bitmap before an operator contains the Roaring bitmap after the operator.

Return type: bool

Example:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
 
SELECT rb_build('{2,3,4}') @> rb_build('{2,3}');
?column?
----------
t
(1 row)
SELECT rb_build('{2,3,4}') @> 4;
?column?
----------
t
(1 row)

<@

Description: Determines whether the Roaring bitmap before an operator is contained in the Roaring bitmap after the operator.

Return type: bool

Example:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
 
SELECT  4 <@ rb_build('{2,3,4}');
?column?
----------
t
(1 row)
SELECT rb_build('{2,3,4}') <@ rb_build('{2,3}');
?column?
----------
f
(1 row)

&&

Description: If two Roaring bitmaps overlap, true is returned. Otherwise, false is returned.

Return type: bool

Example:

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
 
SELECT rb_build('{2,3,4}') && rb_build('{2,3}');
?column?
----------
t
(1 row)
SELECT rb_build('{2,3,4}') && rb_build('{7,8,9}');
?column?
----------
f
(1 row)