count(distinct) returns wrong count when there's FACET

[sanikolaev]

Bug Description:

select count(distinct) ... FACET against a distributed table returns a wrong value.

MRE:

mysql> drop table if exists t; drop table if exists t2; create table t(a int); insert into t values (1,1),(2,2); create table t2 like t; insert into t2 values (4,2); select * from t,t2; select count(distinct a) from t,t2 facet 1;
--------------
drop table if exists t
--------------

Query OK, 0 rows affected (0.02 sec)

--------------
drop table if exists t2
--------------

Query OK, 0 rows affected (0.00 sec)

--------------
create table t(a int)
--------------

Query OK, 0 rows affected (0.00 sec)

--------------
insert into t values (1,1),(2,2)
--------------

Query OK, 2 rows affected (0.00 sec)

--------------
create table t2 like t
--------------

Query OK, 0 rows affected (0.00 sec)

--------------
insert into t2 values (4,2)
--------------

Query OK, 1 row affected (0.00 sec)

--------------
select * from t,t2
--------------

+------+------+
| id   | a    |
+------+------+
|    1 |    1 |
|    4 |    2 |
|    2 |    2 |
+------+------+
3 rows in set (0.00 sec)
--- 3 out of 3 results in 0ms ---

--------------
select count(distinct a) from t,t2 facet 1
--------------

+-------------------+
| count(distinct a) |
+-------------------+
|                 3 |
+-------------------+
1 row in set (0.00 sec)
--- 1 out of 1 results in 0ms ---

+------+----------+
| 1    | count(*) |
+------+----------+
|    1 |        3 |
+------+----------+
1 row in set (0.00 sec)
--- 1 out of 1 results in 0ms ---

Expected:

select count(distinct a) from t,t2 facet 1
--------------

+-------------------+
| count(distinct a) |
+-------------------+
|                 2 |
+-------------------+

+------+----------+
| 1    | count(*) |
+------+----------+
|    1 |        3 |
+------+----------+

Removing FACET solves the issue:

mysql> select count(distinct a) from t,t2;
--------------
select count(distinct a) from t,t2
--------------

+-------------------+
| count(distinct a) |
+-------------------+
|                 2 |
+-------------------+
1 row in set (0.00 sec)
--- 1 out of 1 results in 0ms ---

Manticore Search Version:

Manticore 6.3.1 bc8b773e5@24052416 dev (columnar 2.3.1 4383a90@24052309) (secondary 2.3.1 4383a90@24052309) (knn 2.3.1 4383a90@24052309)

Operating System Version:

Ubuntu Jammy (dev2)

Have you tried the latest development version?

• Yes

Internal Checklist:

^{To be completed by the assignee. Check off tasks that have been completed or are not applicable.}

• Task estimated
• Specification created, reviewed, and approved
• Implementation completed
• Tests developed
• Documentation updated
• Documentation proofread
• Changelog updated