如下sql 用于统计mysql数据库非系统db的全部表/索引信息
(包括：数据库、表名、表注释、表行数、表大小、索引名、索引字段、字段注释、基数、选择性比、索引类型..)
<b>sql：</b>
select t.table_schema db_name,
t.table_name,
t.table_comment 表注释,
t.table_rows 表行数,
round (sum(data_length / 1024 / 1024 ), 2 ) 表大小mb,
-- st.table_id,
-- si.index_id,
s.index_schema,
s.index_name,
s.column_name,
c.column_comment 列注释,
s.cardinality,
concat (round (( case
when s.cardinality = 0 then
1
else
s.cardinality
end ) / (case
when t.table_rows = 0 then
t.table_rows
end ) * 100 ,
2 ),
"%") 选择性,
s.index_type
from information_schema.tables t
join information_schema.innodb_sys_tablestats st
on concat (t.table_schema, "/", t.table_name) = st.name
join information_schema.innodb_sys_indexes si
on si.table_id = st.table_id
join information_schema.statistics s
on si.name = s.index_name
and s.table_name = t.table_name
and t.table_schema = s.table_schema
join information_schema.columns c
on c.column_name = s.column_name
and c.table_name = t.table_name
and c.table_schema = s.table_schema
and t.table_schema not in ( 'test' ,
'mysql' ,
'zabbix' ,
'information_schema' ,
'performance_schema' )
group by t.table_schema,
t.table_name,
t.table_comment,
t.table_rows,
s.index_schema,
s.index_name,
s.column_name,
c.column_comment,
s.cardinality,
s.index_type
order by ( case
when s.cardinality = 0 then
1
else
s.cardinality
end ) / (case
when t.table_rows = 0 then
t.table_rows
end );
<b>官网注释</b>
information_schema 表
the innodb_sys_tablestats provides a view of low-level status information about innodb tables.
this data is used by the mysql optimizer to calculate which index to use when querying an innodb table.
this information is derived from in-memory data structures rather than corresponding to data stored on disk.
there is no corresponding internal innodb system table.
the innodb_sys_indexes table provides metadata about innodb indexes, equivalent to the information in the internal sys_indexes table in the innodb data dictionary.
<b>表/视图 字段介绍</b>
mysql> desc statistics;
+---------------+---------------+------+-----+---------+-------+
| field | type | null | key | default | extra |
| table_catalog | varchar(512) | no | | | |
| table_schema | varchar(64) | no | | | |
| table_name | varchar(64) | no | | | |
| non_unique | bigint(1) | no | | 0 | |
| index_schema | varchar(64) | no | | | |
| index_name | varchar(64) | no | | | |
| seq_in_index | bigint(2) | no | | 0 | |
| column_name | varchar(64) | no | | | |
| collation | varchar(1) | yes | | null | |
| cardinality | bigint(21) | yes | | null | |
| sub_part | bigint(3) | yes | | null | |
| packed | varchar(10) | yes | | null | |
| nullable | varchar(3) | no | | | |
| index_type | varchar(16) | no | | | |
| comment | varchar(16) | yes | | null | |
| index_comment | varchar(1024) | no | | | |
mysql>
mysql> desc columns;
+--------------------------+---------------------+------+-----+---------+-------+
| field | type | null | key | default | extra |
| table_catalog | varchar(512) | no | | | |
| table_schema | varchar(64) | no | | | |
| table_name | varchar(64) | no | | | |
| column_name | varchar(64) | no | | | |
| ordinal_position | bigint(21) unsigned | no | | 0 | |
| column_default | longtext | yes | | null | |
| is_nullable | varchar(3) | no | | | |
| data_type | varchar(64) | no | | | |
| character_maximum_length | bigint(21) unsigned | yes | | null | |
| character_octet_length | bigint(21) unsigned | yes | | null | |
| numeric_precision | bigint(21) unsigned | yes | | null | |
| numeric_scale | bigint(21) unsigned | yes | | null | |
| datetime_precision | bigint(21) unsigned | yes | | null | |
| character_set_name | varchar(32) | yes | | null | |
| collation_name | varchar(32) | yes | | null | |
| column_type | longtext | no | | null | |
| column_key | varchar(3) | no | | | |
| extra | varchar(30) | no | | | |
| privileges | varchar(80) | no | | | |
| column_comment | varchar(1024) | no | | | |
mysql>
mysql> desc innodb_sys_indexes ;
+----------+---------------------+------+-----+---------+-------+
| field | type | null | key | default | extra |
| index_id | bigint(21) unsigned | no | | 0 | |
| name | varchar(193) | no | | | |
| table_id | bigint(21) unsigned | no | | 0 | |
| type | int(11) | no | | 0 | |
| n_fields | int(11) | no | | 0 | |
| page_no | int(11) | no | | 0 | |
| space | int(11) | no | | 0 | |
mysql>
mysql> desc innodb_sys_tablestats ;
+-------------------+---------------------+------+-----+---------+-------+
| field | type | null | key | default | extra |
| table_id | bigint(21) unsigned | no | | 0 | |
| name | varchar(193) | no | | | |
| stats_initialized | varchar(193) | no | | | |
| num_rows | bigint(21) unsigned | no | | 0 | |
| clust_index_size | bigint(21) unsigned | no | | 0 | |
| other_index_size | bigint(21) unsigned | no | | 0 | |
| modified_counter | bigint(21) unsigned | no | | 0 | |
| autoinc | bigint(21) unsigned | no | | 0 | |
| ref_count | int(11) | no | | 0 | |
mysql> desc tables;
+-----------------+---------------------+------+-----+---------+-------+
| field | type | null | key | default | extra |
| table_catalog | varchar(512) | no | | | |
| table_schema | varchar(64) | no | | | |
| table_name | varchar(64) | no | | | |
| table_type | varchar(64) | no | | | |
| engine | varchar(64) | yes | | null | |
| version | bigint(21) unsigned | yes | | null | |
| row_format | varchar(10) | yes | | null | |
| table_rows | bigint(21) unsigned | yes | | null | |
| avg_row_length | bigint(21) unsigned | yes | | null | |
| data_length | bigint(21) unsigned | yes | | null | |
| max_data_length | bigint(21) unsigned | yes | | null | |
| index_length | bigint(21) unsigned | yes | | null | |
| data_free | bigint(21) unsigned | yes | | null | |
| auto_increment | bigint(21) unsigned | yes | | null | |
| create_time | datetime | yes | | null | |
| update_time | datetime | yes | | null | |
| check_time | datetime | yes | | null | |
| table_collation | varchar(32) | yes | | null | |
| checksum | bigint(21) unsigned | yes | | null | |
| create_options | varchar(255) | yes | | null | |
| table_comment | varchar(2048) | no | | | |
【源于本人笔记】 若有书写错误，表达错误，请指正...
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