查询mysql数据库的大小

（1）INFORMATION_SCHEMA
select (sum(data_length) + sum(index_length))/(1024*1024) from INFORMATION_SCHEMA.`TABLES` where table_schema =  'your_table_schema' and table_name like 'your_table_name';
（2）show table status like '';
try {
Class.forName("com.mysql.jdbc.Driver");
Connection conn = DriverManager.getConnection("url", "user", "pwd");
Statement stat = conn.createStatement();
stat.executeUpdate("use your_db");
String sql = "show table status like 'your_table_name'";
ResultSet rs = stat.executeQuery(sql);
while (rs.next()) {
for (int i = 0; i < rs.getMetaData().getColumnCount(); i++) {
System.out.print(rs.getString(i + 1) + " ");
}
System.out.println();
}
} catch (Exception e) {
e.printStackTrace();
}
以上的代码会打印出表的相关信息，将相关字段相加即可。