Check Database and Table Space in MySQL

 

Database Space Usage Report

SELECT s.schema_name, CONCAT(IFNULL(ROUND((SUM(t.data_length)+SUM(t.index_length))/1024/1024,2),0.00),"Mb") total_size, CONCAT(IFNULL(ROUND(((SUM(t.data_length)+SUM(t.index_length))-SUM(t.data_free))/1024/1024,2),0.00),"Mb") data_used, CONCAT(IFNULL(ROUND(SUM(data_free)/1024/1024,2),0.00),"Mb") data_free, IFNULL(ROUND((((SUM(t.data_length)+SUM(t.index_length))-SUM(t.data_free))/((SUM(t.data_length)+SUM(t.index_length)))*100),2),0) pct_used FROM INFORMATION_SCHEMA.SCHEMATA s, INFORMATION_SCHEMA.TABLES t WHERE s.schema_name = t.table_schema GROUP BY s.schema_name ORDER BY total_size DESC

Table Space Usage Report

SELECT s.schema_name, table_name, CONCAT(IFNULL(ROUND((SUM(t.data_length)+SUM(t.index_length))/1024/1024,2),0.00),"Mb") total_size, CONCAT(IFNULL(ROUND(((SUM(t.data_length)+SUM(t.index_length))-SUM(t.data_free))/1024/1024,2),0.00),"Mb") data_used, CONCAT(IFNULL(ROUND(SUM(data_free)/1024/1024,2),0.00),"Mb") data_free, IFNULL(ROUND((((SUM(t.data_length)+SUM(t.index_length))-SUM(t.data_free))/((SUM(t.data_length)+SUM(t.index_length)))*100),2),0) pct_used FROM INFORMATION_SCHEMA.SCHEMATA s, INFORMATION_SCHEMA.TABLES t WHERE s.schema_name = t.table_schema GROUP BY s.schema_name, table_name ORDER BY total_size DESC

Check for Tables that have Free Space

SELECT s.schema_name, table_name, IFNULL(ROUND(SUM(data_free)/1024,2),0.00) data_free FROM INFORMATION_SCHEMA.SCHEMATA s, INFORMATION_SCHEMA.TABLES t WHERE s.schema_name = t.table_schema GROUP BY s.schema_name, table_name HAVING data_free > 100 ORDER BY data_free DESC

This SQL will check for all objects with free space. It will display tables with any more than 100Kb of free space so you may want to tweak the having clause, but the idea is that it can spot tables which may benefit from an Optimize Table command.