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SET @default_storage_engine_old = @@session.default_storage_engine;
SET SESSION default_storage_engine = INNODB;
FLUSH INDEX_STATISTICS;
FLUSH TABLE_STATISTICS;
SET @userstat_old= @@userstat;
SET GLOBAL userstat=ON;
CREATE TABLE t1 (id int(10), PRIMARY KEY (id));
INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
FLUSH TABLE_STATISTICS;
SELECT SUM(id) FROM t1;
SUM(id)
55
SELECT ROWS_READ FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
10
SELECT ROWS_READ FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
SELECT PAGES_ACCESSED, PAGES_READ_FROM_DISK FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t1';
PAGES_ACCESSED PAGES_READ_FROM_DISK
1 0
FLUSH TABLE_STATISTICS;
SELECT ROWS_READ FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
SELECT ROWS_READ FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
FLUSH INDEX_STATISTICS;
SELECT ROWS_READ FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
SELECT COUNT(*) FROM t1;
COUNT(*)
10
SELECT ROWS_READ FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
10
SELECT ROWS_READ FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
DROP TABLE t1;
CREATE TABLE t2 (c1 INT UNSIGNED);
ALTER TABLE t2 MODIFY c1 FLOAT;
SELECT * FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t2';
TABLE_SCHEMA TABLE_NAME ROWS_READ ROWS_CHANGED ROWS_CHANGED_X_INDEXES ROWS_INSERTED ROWS_UPDATED ROWS_DELETED KEY_READ_HITS KEY_READ_MISSES PAGES_ACCESSED PAGES_READ_FROM_DISK
DROP TABLE t2;
CREATE TABLE t2 (c1 INT UNSIGNED);
ALTER TABLE t2 MODIFY c1 FLOAT;
SELECT * FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t2';
TABLE_SCHEMA TABLE_NAME ROWS_READ ROWS_CHANGED ROWS_CHANGED_X_INDEXES ROWS_INSERTED ROWS_UPDATED ROWS_DELETED KEY_READ_HITS KEY_READ_MISSES PAGES_ACCESSED PAGES_READ_FROM_DISK
DROP TABLE t2;
SET GLOBAL userstat= @userstat_old;
SET SESSION default_storage_engine = @default_storage_engine_old;
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