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#
# Bug #27454796 - WRONG GROUP BY RESULTS WITH TEMPTABLE AND NO PAD COLLATIONS
#
# Notes:
# - The TRIM is used below as it cannot be predicted which rows
# would be selected by GROUP BY and VARCHAR columns preserves
# the spaces.
# - SELECTs with GROUP test indexes with HASH algorithm.
# - SELECTs with subqueries test indexes with BTREE algorithm.
#
--echo #
--echo # Prepare
--echo #
SET @big_tables_saved = @@big_tables;
SET @optimizer_switch_saved = @@optimizer_switch;
--echo #
--echo # Check if selected collations have required padding mode
--echo #
SELECT pad_attribute FROM information_schema.collations
WHERE collation_name = 'utf8mb4_0900_ai_ci';
SELECT pad_attribute FROM information_schema.collations
WHERE collation_name = 'utf8mb4_general_ci';
--echo #
--echo # Create test tables
--echo #
CREATE TABLE table_char_no_pad (
f1 CHAR(20) COLLATE utf8mb4_0900_ai_ci
);
INSERT INTO table_char_no_pad VALUES ('ABC ');
INSERT INTO table_char_no_pad VALUES ('XYZ');
INSERT INTO table_char_no_pad VALUES ('XYZ ');
INSERT INTO table_char_no_pad VALUES ('ABC ');
CREATE TABLE table_varchar_no_pad (
f1 VARCHAR(20) COLLATE utf8mb4_0900_ai_ci
);
INSERT INTO table_varchar_no_pad VALUES ('ABC ');
INSERT INTO table_varchar_no_pad VALUES ('XYZ');
INSERT INTO table_varchar_no_pad VALUES ('XYZ ');
INSERT INTO table_varchar_no_pad VALUES ('ABC ');
CREATE TABLE table_char_pad_space (
f1 CHAR(20) COLLATE utf8mb4_general_ci
);
INSERT INTO table_char_pad_space VALUES ('ABC ');
INSERT INTO table_char_pad_space VALUES ('XYZ');
INSERT INTO table_char_pad_space VALUES ('XYZ ');
INSERT INTO table_char_pad_space VALUES ('ABC ');
CREATE TABLE table_varchar_pad_space (
f1 VARCHAR(20) COLLATE utf8mb4_general_ci
);
INSERT INTO table_varchar_pad_space VALUES ('ABC ');
INSERT INTO table_varchar_pad_space VALUES ('XYZ');
INSERT INTO table_varchar_pad_space VALUES ('XYZ ');
INSERT INTO table_varchar_pad_space VALUES ('ABC ');
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_tables';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_disk_tables';
--echo #
--echo # Disable optimization to force creating BTREE indexes.
--echo #
SET @@optimizer_switch = "derived_merge=off";
--echo #
--echo # Test with Temptable engine
--echo #
SET SESSION big_tables = 0;
SET @@internal_tmp_mem_storage_engine = TempTable;
--sorted_result
SELECT f1, COUNT(*) FROM table_varchar_no_pad GROUP BY f1;
--sorted_result
SELECT f1, COUNT(*) FROM table_char_no_pad GROUP BY f1;
--sorted_result
SELECT TRIM(f1), COUNT(*) FROM table_varchar_pad_space GROUP BY f1;
--sorted_result
SELECT f1, COUNT(*) FROM table_char_pad_space GROUP BY f1;
--sorted_result
SELECT f1 FROM (SELECT * FROM table_varchar_no_pad) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_char_no_pad) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_varchar_pad_space) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_char_pad_space) AS dt WHERE f1 = 'ABC';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_tables';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_disk_tables';
--echo #
--echo # Test with Heap engine
--echo #
SET SESSION big_tables = 0;
SET @@internal_tmp_mem_storage_engine = MEMORY;
--sorted_result
SELECT f1, COUNT(*) FROM table_varchar_no_pad GROUP BY f1;
--sorted_result
SELECT f1, COUNT(*) FROM table_char_no_pad GROUP BY f1;
--sorted_result
SELECT TRIM(f1), COUNT(*) FROM table_varchar_pad_space GROUP BY f1;
--sorted_result
SELECT f1, COUNT(*) FROM table_char_pad_space GROUP BY f1;
--sorted_result
SELECT f1 FROM (SELECT * FROM table_varchar_no_pad) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_char_no_pad) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_varchar_pad_space) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_char_pad_space) AS dt WHERE f1 = 'ABC';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_tables';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_disk_tables';
-- echo #
-- echo # Restore default engine
-- echo #
SET @@internal_tmp_mem_storage_engine = default;
--echo #
--echo # Test with disk temp table engine
--echo #
SET SESSION big_tables = 1;
--sorted_result
SELECT f1, COUNT(*) FROM table_varchar_no_pad GROUP BY f1;
--sorted_result
SELECT f1, COUNT(*) FROM table_char_no_pad GROUP BY f1;
--sorted_result
SELECT TRIM(f1), COUNT(*) FROM table_varchar_pad_space GROUP BY f1;
--sorted_result
SELECT f1, COUNT(*) FROM table_char_pad_space GROUP BY f1;
--sorted_result
SELECT f1 FROM (SELECT * FROM table_varchar_no_pad) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_char_no_pad) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_varchar_pad_space) AS dt WHERE f1 = 'ABC';
--sorted_result
SELECT f1 FROM (SELECT * FROM table_char_pad_space) AS dt WHERE f1 = 'ABC';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_tables';
--skip_if_hypergraph # Depends on the query plan.
SHOW STATUS LIKE 'Created_tmp_disk_tables';
--echo #
--echo # Cleanup
--echo #
SET SESSION big_tables = @big_tables_saved;
SET @@optimizer_switch = @optimizer_switch_saved;
DROP TABLE table_varchar_no_pad;
DROP TABLE table_char_no_pad;
DROP TABLE table_varchar_pad_space;
DROP TABLE table_char_pad_space;
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