#
# Various tests for SUM(DISTINCT ...)
#

--source include/big_test.inc
--source include/have_innodb.inc
--source include/have_sequence.inc

set @save_tmp_table_size=@@tmp_table_size;
set @save_max_heap_table_size=@@max_heap_table_size;

#
# Test the case when distinct values doesn't fit in memory and 
# filesort is used (see uniques.cc:merge_walk)
#

set storage_engine=MYISAM;

CREATE TABLE t1 (id INTEGER);
CREATE TABLE t2 (id INTEGER);

INSERT INTO t1 SELECT b.seq FROM seq_1_to_128,seq_1_to_1024 b;

# Just test that AVG(DISTINCT) is there
SELECT AVG(DISTINCT id) FROM t1 GROUP BY id % 13;
SELECT SUM(DISTINCT id)/COUNT(DISTINCT id) FROM t1 GROUP BY id % 13;

INSERT INTO t1 SELECT b.seq FROM seq_1_to_128,seq_1025_to_16384 b;
INSERT INTO t2 SELECT b.seq FROM seq_1_to_128 a,seq_1_to_16384 b
ORDER by (a.seq*0+b.seq)*rand();

# SELECT '++++++++++++++++++++++++++++++++++++++++++++++++++';

SELECT SUM(DISTINCT id) sm FROM t1;
SELECT SUM(DISTINCT id) sm FROM t2;
SELECT SUM(DISTINCT id) sm FROM t1 group by id % 13;

# this limit for max_heap_table_size is set to force testing the case, when
# all distinct sum values can not fit in memory and must be stored in a
# temporary table

SET max_heap_table_size=16384;

# to check that max_heap_table_size was actually set (hard limit for minimum
# max_heap_table_size is set in mysqld.cc):

SHOW variables LIKE 'max_heap_table_size';

SELECT SUM(DISTINCT id) sm FROM t1;
SELECT SUM(DISTINCT id) sm FROM t2;
SELECT SUM(DISTINCT id) sm FROM t1 GROUP BY id % 13;

--echo # 
--echo # Bug mdev-4063: SUM(DISTINCT...) with small'max_heap_table_size 
--echo # (bug #56927)
--echo # 

SET max_heap_table_size=default;

INSERT INTO t1 SELECT b.seq FROM seq_1_to_128,seq_16385_to_32768 b;
TRUNCATE t2;
INSERT INTO t2 SELECT b.seq FROM seq_1_to_128 a,seq_1_to_32768 b
ORDER BY (a.seq*0+b.seq)*rand();

SELECT SUM(DISTINCT id) sm FROM t2;

SET max_heap_table_size=16384;

SELECT SUM(DISTINCT id) sm FROM t2;

DROP TABLE t1;
DROP TABLE t2;

SET @@tmp_table_size=@save_tmp_table_size;
SET @@max_heap_table_size=@save_max_heap_table_size;

--echo #
--echo # MDEV-4311: COUNT(DISTINCT...) requiring a file for UNIQUE (bug #68749)
--echo #
CREATE TABLE t2 (id INTEGER) ENGINE=InnoDB;

BEGIN;
INSERT INTO t2 SELECT b.seq FROM seq_1_to_128 a, seq_1_to_16384 b
ORDER BY b.seq*rand();
INSERT INTO t2 VALUE(NULL);

--echo # With default tmp_table_size / max_heap_table_size
SELECT SQL_NO_CACHE count(DISTINCT id) sm FROM t2;

set @@tmp_table_size=1024*256;

--echo # With reduced tmp_table_size
SELECT SQL_NO_CACHE count(DISTINCT id) sm FROM t2;

set @@tmp_table_size=@save_tmp_table_size;
SET @@max_heap_table_size=1024*256;

--echo # With reduced max_heap_table_size
SELECT SQL_NO_CACHE count(DISTINCT id) sm FROM t2;

SET @@max_heap_table_size=@save_max_heap_table_size;

--echo # Back to default tmp_table_size / max_heap_table_size
SELECT SQL_NO_CACHE count(DISTINCT id) sm FROM t2;
COMMIT;

DROP TABLE t2;