Maths Server Using Socket Programming

It is time to implement a more comprehensive network application by using the socket programming APIs you have learned so far. A sample math client-server interaction demonstrating online math server that can perform basic math operations,

package com.techa2zsolution.intf.math;

public interface MathService {
    public double add(double firstValue, double secondValue);
    public double sub(double firstValue, double secondValue);
    public double div(double firstValue, double secondValue);
    public double mul(double firstValue, double secondValue);
}

Get the database size, Free space and last update

To get the current database size just by querying into your query browser or CLI from the INFORMATION_SCHEMA database in table TABLES.

SELECT table_schema "Data Base Name",
sum( data_length + index_length ) / 1024 / 1024 "Data Base Size in MB"
FROM information_schema.TABLES
GROUP BY table_schema ;

Get the database free space

SELECT table_schema "Data Base Name",
sum( data_length + index_length ) / 1024 / 1024 "Data Base Size in MB",
sum( data_free )/ 1024 / 1024 "Free Space in MB"
FROM information_schema.TABLES
GROUP BY table_schema;

Get the database last update ordered by update time then by create time.

SELECT MAX(UPDATE_TIME), MAX(CREATE_TIME), TABLE_SCHEMA
FROM `TABLES`
GROUP BY TABLE_SCHEMA
ORDER BY 1, 2;