- Categories:
Aggregate functions (Boolean) , Window functions , Conditional expression functions
BOOLXOR_AGG¶
Returns TRUE if exactly one Boolean record in the group evaluates to TRUE.
If all records in the group are NULL, or if the group is empty, the function returns NULL.
- See also:
Syntax¶
Aggregate function
BOOLXOR_AGG( <expr> )
Window function
BOOLXOR_AGG( <expr> ) OVER ( [ PARTITION BY <partition_expr> ] )
Arguments¶
expr
The input expression must be an expression that can be evaluated to a boolean or converted to a boolean.
partition_expr
This column or expression specifies how to separate the input into partitions (sub-windows).
Returns¶
The data type of the returned value is BOOLEAN.
Usage notes¶
Numeric values are converted to
TRUE
if they are non-zero.Character/text types are not supported as they cannot be converted to Boolean.
When this function is called as a window function, it does not support:
An ORDER BY clause within the OVER clause.
Explicit window frames.
Examples¶
The following example shows that boolxor_agg returns true when exactly one of the input values is true.
Create and load the table:
create or replace table test_boolean_agg( id integer, c1 boolean, c2 boolean, c3 boolean, c4 boolean ); insert into test_boolean_agg (id, c1, c2, c3, c4) values (1, true, true, true, false), (2, true, false, false, false), (3, true, true, false, false), (4, true, false, false, false);Display the data:
select * from test_boolean_agg; +----+------+-------+-------+-------+ | ID | C1 | C2 | C3 | C4 | |----+------+-------+-------+-------| | 1 | True | True | True | False | | 2 | True | False | False | False | | 3 | True | True | False | False | | 4 | True | False | False | False | +----+------+-------+-------+-------+Query the data:
select boolxor_agg(c1), boolxor_agg(c2), boolxor_agg(c3), boolxor_agg(c4) from test_boolean_agg; +-----------------+-----------------+-----------------+-----------------+ | BOOLXOR_AGG(C1) | BOOLXOR_AGG(C2) | BOOLXOR_AGG(C3) | BOOLXOR_AGG(C4) | |-----------------+-----------------+-----------------+-----------------| | False | False | True | False | +-----------------+-----------------+-----------------+-----------------+
Window function
This example is similar to the previous example, but it shows usage as a window function, with the input rows split into two partitions (one for IDs greater than 0 and one for IDs less than or equal to 0). Additional data was added to the table.
Add rows to the table:
insert into test_boolean_agg (id, c1, c2, c3, c4) values (-4, false, false, false, true), (-3, false, true, true, true), (-2, false, false, true, true), (-1, false, true, true, true);Display the data:
select * from test_boolean_agg order by id; +----+-------+-------+-------+-------+ | ID | C1 | C2 | C3 | C4 | |----+-------+-------+-------+-------| | -4 | False | False | False | True | | -3 | False | True | True | True | | -2 | False | False | True | True | | -1 | False | True | True | True | | 1 | True | True | True | False | | 2 | True | False | False | False | | 3 | True | True | False | False | | 4 | True | False | False | False | +----+-------+-------+-------+-------+Query the data:
select id, boolxor_agg(c1) OVER (PARTITION BY (id > 0)), boolxor_agg(c2) OVER (PARTITION BY (id > 0)), boolxor_agg(c3) OVER (PARTITION BY (id > 0)), boolxor_agg(c4) OVER (PARTITION BY (id > 0)) from test_boolean_agg order by id; +----+----------------------------------------------+----------------------------------------------+----------------------------------------------+----------------------------------------------+ | ID | BOOLXOR_AGG(C1) OVER (PARTITION BY (ID > 0)) | BOOLXOR_AGG(C2) OVER (PARTITION BY (ID > 0)) | BOOLXOR_AGG(C3) OVER (PARTITION BY (ID > 0)) | BOOLXOR_AGG(C4) OVER (PARTITION BY (ID > 0)) | |----+----------------------------------------------+----------------------------------------------+----------------------------------------------+----------------------------------------------| | -4 | False | False | False | False | | -3 | False | False | False | False | | -2 | False | False | False | False | | -1 | False | False | False | False | | 1 | False | False | True | False | | 2 | False | False | True | False | | 3 | False | False | True | False | | 4 | False | False | True | False | +----+----------------------------------------------+----------------------------------------------+----------------------------------------------+----------------------------------------------+
Error example
If this function is passed strings that cannot be converted to Boolean, the function will give an error:
select boolxor_agg('invalid type');
100037 (22018): Boolean value 'invalid_type' is not recognized