config root man

CREATE TABLE test_ps_fetch
(a INT, b INT, c INT, d INT, PRIMARY KEY (a, b), INDEX idx (c, d))
ENGINE=INNODB STATS_PERSISTENT=1;
ANALYZE TABLE test_ps_fetch;
Table	test.test_ps_fetch
Op	analyze
Msg_type	status
Msg_text	OK
SELECT n_rows, clustered_index_size, sum_of_other_index_sizes
FROM mysql.innodb_table_stats WHERE table_name = 'test_ps_fetch';
n_rows	0
clustered_index_size	1
sum_of_other_index_sizes	1
SELECT index_name, stat_name, stat_value, sample_size, stat_description
FROM mysql.innodb_index_stats WHERE table_name = 'test_ps_fetch'
ORDER BY index_name, stat_name;
index_name	PRIMARY
stat_name	n_diff_pfx01
stat_value	0
sample_size	1
stat_description	a
index_name	PRIMARY
stat_name	n_diff_pfx02
stat_value	0
sample_size	1
stat_description	a,b
index_name	PRIMARY
stat_name	n_leaf_pages
stat_value	1
sample_size	NULL
stat_description	Number of leaf pages in the index
index_name	PRIMARY
stat_name	size
stat_value	1
sample_size	NULL
stat_description	Number of pages in the index
index_name	idx
stat_name	n_diff_pfx01
stat_value	0
sample_size	1
stat_description	c
index_name	idx
stat_name	n_diff_pfx02
stat_value	0
sample_size	1
stat_description	c,d
index_name	idx
stat_name	n_diff_pfx03
stat_value	0
sample_size	1
stat_description	c,d,a
index_name	idx
stat_name	n_diff_pfx04
stat_value	0
sample_size	1
stat_description	c,d,a,b
index_name	idx
stat_name	n_leaf_pages
stat_value	1
sample_size	NULL
stat_description	Number of leaf pages in the index
index_name	idx
stat_name	size
stat_value	1
sample_size	NULL
stat_description	Number of pages in the index
SELECT index_name, seq_in_index, column_name, cardinality
FROM information_schema.statistics WHERE table_name = 'test_ps_fetch'
ORDER BY index_name, seq_in_index;
index_name	idx
seq_in_index	1
column_name	c
cardinality	0
index_name	idx
seq_in_index	2
column_name	d
cardinality	0
index_name	PRIMARY
seq_in_index	1
column_name	a
cardinality	0
index_name	PRIMARY
seq_in_index	2
column_name	b
cardinality	0
SELECT
table_rows, avg_row_length, max_data_length, index_length
FROM information_schema.tables WHERE table_name = 'test_ps_fetch';
table_rows	0
avg_row_length	0
max_data_length	0
index_length	16384
UPDATE mysql.innodb_table_stats SET
n_rows = 1000,
clustered_index_size = 5
WHERE
table_name = 'test_ps_fetch';
UPDATE mysql.innodb_index_stats SET
stat_value = 20
WHERE
table_name = 'test_ps_fetch' AND
index_name = 'PRIMARY' AND
stat_name = 'n_diff_pfx01';
UPDATE mysql.innodb_index_stats SET
stat_value = 90
WHERE
table_name = 'test_ps_fetch' AND
index_name = 'PRIMARY' AND
stat_name = 'n_diff_pfx02';
UPDATE mysql.innodb_index_stats SET
stat_value = 3
WHERE
table_name = 'test_ps_fetch' AND
index_name = 'idx' AND
stat_name = 'n_diff_pfx01';
UPDATE mysql.innodb_index_stats SET
stat_value = 11
WHERE
table_name = 'test_ps_fetch' AND
index_name = 'idx' AND
stat_name = 'n_diff_pfx02';
FLUSH TABLE test_ps_fetch;
SELECT seq_in_index, column_name, cardinality
FROM information_schema.statistics WHERE table_name = 'test_ps_fetch'
ORDER BY index_name, seq_in_index;
seq_in_index	1
column_name	c
cardinality	3
seq_in_index	2
column_name	d
cardinality	11
seq_in_index	1
column_name	a
cardinality	20
seq_in_index	2
column_name	b
cardinality	90
SELECT
table_rows, avg_row_length, max_data_length, index_length
FROM information_schema.tables WHERE table_name = 'test_ps_fetch';
table_rows	1000
avg_row_length	81
max_data_length	0
index_length	16384
DROP TABLE test_ps_fetch;