mariadb/mysql-test/main/distinct_notembedded.test

# Embedded doesn't have optimizer trace:
--source include/not_embedded.inc
--source include/have_sequence.inc

--echo #
--echo # MDEV-30660 COUNT DISTINCT seems unnecessarily slow when run on a PK
--echo #

#Enable after fix MDEV-32034
--disable_view_protocol
set @save_optimizer_trace = @@optimizer_trace;
SET optimizer_trace='enabled=on';
let $trace=
SELECT JSON_DETAILED(JSON_EXTRACT(trace, '\$**.prepare_sum_aggregators')) AS JS
  FROM INFORMATION_SCHEMA.OPTIMIZER_TRACE;

CREATE TABLE t1 (a INT NOT NULL PRIMARY KEY, b INT NOT NULL);
INSERT INTO t1 VALUES (1,1), (2,1), (3,1);

--echo # Optimization is applied (aggregator=simple):
SELECT COUNT(DISTINCT a) FROM t1;
eval $trace;

SELECT AVG(DISTINCT a), SUM(DISTINCT b) FROM t1;
eval $trace;

--echo # Only `a` is unique but it's enough to eliminate DISTINCT:
SELECT COUNT(DISTINCT b, a) FROM t1;
eval $trace;

SELECT COUNT(DISTINCT a, a + b) FROM t1;
eval $trace;

SELECT SUM(DISTINCT a), AVG(DISTINCT a), COUNT(DISTINCT a) FROM t1 WHERE a > 1;
eval $trace;

--echo # Optimization is not applied 'cause function argument is not a field
--echo # (aggregator=distinct):
SELECT SUM(DISTINCT a + b) FROM t1;
eval $trace;

SELECT COUNT(DISTINCT b) FROM t1;
eval $trace;

SELECT AVG(DISTINCT b / a) FROM t1;
eval $trace;

EXPLAIN SELECT COUNT(DISTINCT (SELECT a)) FROM t1;
eval $trace;

CREATE TABLE t2 (a INT);
INSERT INTO t2 VALUES (1), (2);

--echo # Optimization is not applied 'cause there is more than one table
SELECT COUNT(DISTINCT t1.a) FROM t1, t2;
eval $trace;

SELECT AVG(DISTINCT t1.a) FROM t1, t2;
eval $trace;

--echo # Const tables, optimization is applied
SELECT COUNT(DISTINCT a) FROM t1, (SELECT 1) AS t2;
eval $trace;

SELECT AVG(DISTINCT t1.a) FROM (SELECT 1 AS a) AS t2, t1, (SELECT 2 AS a) AS t3;
eval $trace;

SELECT COUNT(DISTINCT a) FROM t1, (SELECT 1 UNION SELECT 2) AS t2;
eval $trace;

--echo # Unique index on two columns
CREATE TABLE t3 (a INT NOT NULL, b INT NOT NULL);
INSERT INTO t3 VALUES (1,1), (1,2), (1,3), (2,1), (2,2), (3,1), (3,2);
CREATE UNIQUE INDEX t3_a_b ON t3 (a, b);
--echo # Optimization is applied:
SELECT COUNT(DISTINCT a, b) FROM t3;
eval $trace;

SELECT COUNT(DISTINCT b, a) FROM t3;
eval $trace;

SELECT COUNT(DISTINCT b, a) FROM t3 WHERE a < 3;
eval $trace;

--echo # Optimization is applied to one of the functions:
SELECT COUNT(DISTINCT b), SUM(DISTINCT a), SUM(DISTINCT a + b) FROM t3 GROUP BY a;
eval $trace;

--echo # Can't apply optimization 'cause GROUP BY argument is not a field:
SELECT COUNT(DISTINCT b) FROM t3 GROUP BY a+b;
eval $trace;

--echo # Test merged view
CREATE VIEW v1 AS SELECT * FROM t1;
--echo # Optimization is applied
SELECT COUNT(DISTINCT a, b) FROM v1;
eval $trace;

--echo # GROUP_CONCAT implements non-standard distinct aggregator
SELECT GROUP_CONCAT(b) FROM t1;
eval $trace;

SELECT GROUP_CONCAT(DISTINCT b) FROM t1;
eval $trace;

DROP TABLE t1, t2, t3;
DROP VIEW v1;
SET optimizer_trace = @save_optimizer_trace;
--enable_view_protocol

--echo #
--echo # end of 10.5 tests
--echo #