# # Various tests for SUM(DISTINCT ...) # --source include/big_test.inc --disable_warnings DROP TABLE IF EXISTS t1, t2; --enable_warnings # # Test the case when distinct values doesn't fit in memory and # filesort is used (see uniques.cc:merge_walk) # CREATE TABLE t1 (id INTEGER); CREATE TABLE t2 (id INTEGER); INSERT INTO t1 (id) VALUES (1), (1), (1),(1); INSERT INTO t1 (id) SELECT id FROM t1; /* 8 */ INSERT INTO t1 (id) SELECT id FROM t1; /* 12 */ INSERT INTO t1 (id) SELECT id FROM t1; /* 16 */ INSERT INTO t1 (id) SELECT id FROM t1; /* 20 */ INSERT INTO t1 (id) SELECT id FROM t1; /* 24 */ INSERT INTO t1 SELECT id+1 FROM t1; INSERT INTO t1 SELECT id+2 FROM t1; INSERT INTO t1 SELECT id+4 FROM t1; INSERT INTO t1 SELECT id+8 FROM t1; INSERT INTO t1 SELECT id+16 FROM t1; INSERT INTO t1 SELECT id+32 FROM t1; INSERT INTO t1 SELECT id+64 FROM t1; INSERT INTO t1 SELECT id+128 FROM t1; INSERT INTO t1 SELECT id+256 FROM t1; INSERT INTO t1 SELECT id+512 FROM t1; # 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 id+1024 FROM t1; INSERT INTO t1 SELECT id+2048 FROM t1; INSERT INTO t1 SELECT id+4096 FROM t1; INSERT INTO t1 SELECT id+8192 FROM t1; INSERT INTO t2 SELECT id FROM t1 ORDER BY id*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; DROP TABLE t1; DROP TABLE t2;