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MDEV-22851: Engine independent index statistics are incorrect for large tables on Windows

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An oveflow was happening on windows because on Windows sizeof(ulong) is 4 bytes
while it is 8 bytes on Linux.
Switched avg_frequency and avg length for column statistics to ulonglong.
Switched avg_frequency for index statistics to ulonglong.
This commit is contained in:
Varun Gupta
2020-07-14 12:09:10 +05:30
parent 67a03b7c94
commit dfdfeecb03
4 changed files with 67 additions and 15 deletions
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29
mysql-test/r/stat_tables_innodb.result
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@ -770,4 +770,33 @@ set @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selecti
set @save_optimizer_switch=@@optimizer_switch;
set use_stat_tables=@save_use_stat_tables;
set optimizer_switch=@save_optimizer_switch_for_stat_tables_test;
#
# MDEV-22851: Engine independent index statistics are incorrect for large tables on Windows.
#
CREATE TABLE t1 AS SELECT TABLE_CATALOG FROM INFORMATION_SCHEMA.COLUMNS;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
SET @save_use_stat_tables= @@use_stat_tables;
SET use_stat_tables= preferably;
SELECT count(*) FROM t1;
count(*)
54336
CREATE INDEX idx ON t1(TABLE_CATALOG);
Warnings:
Warning 1071 Specified key was too long; max key length is 767 bytes
ANALYZE TABLE t1 PERSISTENT FOR COLUMNS (TABLE_CATALOG) INDEXES (idx);
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
SELECT * FROM mysql.index_stats where table_name='t1';
db_name table_name index_name prefix_arity avg_frequency
test t1 idx 1 NULL
SELECT * FROM mysql.column_stats where table_name='t1';
db_name table_name column_name min_value max_value nulls_ratio avg_length avg_frequency hist_size hist_type histogram
test t1 TABLE_CATALOG def def 0.0000 3.0000 54336.0000 0 NULL NULL
SET use_stat_tables= @save_use_stat_tables;
DROP TABLE t1;
SET SESSION STORAGE_ENGINE=DEFAULT;