Question

I am dealing with a database that has about 300 tables and I am looking for a way to find all tables that have NO indexes (excluding PRIMARY). Ideally I would like to get back a result set that gives me a count of the number of indexes per table. I have tried this using a query like this:

SELECT 
  table_name, column_name, index_name, count(table_name) as index_count 
FROM 
  information_schema.statistics 
WHERE 
  index_name != 'primary' 
AND
  table_schema = 'your_database'
GROUP BY
  table_name

but it does not return accurate results. any help would be appreciated

Answer 1

this will result those tables that have no indexes at all (not even primary key)

select * from INFORMATION_SCHEMA.tables
where table_schema = 'your_database'
and table_name not in 
(
select  table_name -- , count(*) 
from (
SELECT  table_name, index_name
FROM information_schema.statistics 
WHERE table_schema = 'your_database'
GROUP BY  table_name, index_name) tab_ind_cols
group by table_name
)