Analyse useless MySQL indexes

analyze.sql

-- source: http://de.slideshare.net/techdude/how-to-kill-mysql-performance page 40
SELECT
  t.TABLE_SCHEMA
  , t.TABLE_NAME
  , s.INDEX_NAME
  , s.COLUMN_NAME
  , s.SEQ_IN_INDEX
  , (
    SELECT 
      MAX(SEQ_IN_INDEX) 
    FROM 
      INFORMATION_SCHEMA.STATISTICS s2 
    WHERE 
      s.TABLE_SCHEMA = s2.TABLE_SCHEMA 
      AND s.TABLE_NAME = s2.TABLE_NAME 
      AND s.INDEX_NAME = s2.INDEX_NAME
  ) AS `COLS_IN_INDEX`
  , s.CARDINALITY AS "CARD"
  , t.TABLE_ROWS AS "ROWS"
  , ROUND(((s.CARDINALITY / IFNULL(t.TABLE_ROWS, 0.01)) * 100), 2) AS `SEL %`
FROM
  INFORMATION_SCHEMA.STATISTICS s 
  INNER JOIN INFORMATION_SCHEMA.TABLES t 
    ON s.TABLE_SCHEMA = t.TABLE_SCHEMA AND s.TABLE_NAME = t.TABLE_NAME 
WHERE 
  t.TABLE_SCHEMA = 'DBNAME' 
  AND t.TABLE_ROWS > 10 
  AND s.CARDINALITY IS NOT NULL 
  AND (s.CARDINALITY / IFNULL(t.TABLE_ROWS, 0.01)) < 1.00 
ORDER BY 
  `SEL %`, 
  TABLE_SCHEMA, 
  TABLE_NAME
LIMIT
  10;