SELECT
t.TABLE_SCHEMA,t.TABLE_NAME,INDEX_NAME, CARDINALITY,
TABLE_ROWS, CARDINALITY/TABLE_ROWS AS SELECTIVITY
FROM
information_schema.TABLES t,
(
SELECT table_schema,table_name,index_name,cardinality
FROM information_schema.STATISTICS
WHERE (table_schema,table_name,index_name,seq_in_index) IN (
SELECT table_schema,table_name,index_name,MAX(seq_in_index)
FROM information_schema.STATISTICS
GROUP BY table_schema , table_name , index_name )
) s
WHERE
t.table_schema = s.table_schema
AND t.table_name = s.table_name AND t.table_rows != 0
AND t.table_schema NOT IN ( 'mysql','performance_schema','information_schema')
ORDER BY SELECTIVITY;
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