How do I upload the sensor data from arduino into a database?

Question

I have just connected a Libelium shield to connect many sensors to Arduino UNO, that measure water ph level, temperature,...etc. I really couldn't figure out how do I upload the sensor data into a database(MySQL). I have the code for database connectivity, but still couldn't figure out how(Querying) to upload the sensor data into the database.

The main problem here is how do I make the arduino recognize the sensor data to upload it into database or send to to another Arduino or Raspberry pi through XBee.

Code for database connectivity:

void sendData(){

          Serial.println("Connecting...");
          if (my_conn.mysql_connect(server_addr, 3306, user, password)){
            delay(500);
            Serial.println("Starting SQL!");
            Serial.println(INSERT_SQL);
            my_conn.cmd_query(INSERT_SQL);
            Serial.println("Query Success!");
            my_conn.disconnect();
            Serial.println("\n");
          } 
          else {
            Serial.println("Connection failed!");
          }
}

Answer 1

First you have to create the table in your MySQL database, like:

CREATE TABLE IF NOT EXISTS `table_log` (
  `log_id` int(11) NOT NULL AUTO_INCREMENT,
  `log_date` date NOT NULL,
  `log_time` time NOT NULL,
  `log_t1` float NOT NULL,
  `log_t2` float NOT NULL,
  `log_t3` float NOT NULL,
  `log_t4` float NOT NULL,
  `log_vbatt` float NOT NULL,
  PRIMARY KEY (`log_id`)
) ENGINE=MyISAM  DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci AUTO_INCREMENT=1; 

You can execute it in your phpmyadmin page (or create the table manually there). Above we have columns for auto-increment id ('log_id' - necessary), date & time, 4 temperature values and voltage value (modify these according your requirements).

Than the query to create a new record would be like this:

INSERT INTO `table_log` (`log_id`, `log_date`, `log_time`, `log_t1`, `log_t2`, `log_t3`, `log_t4`, `log_vbatt`) VALUES
    (0, '2016-03-04', '01:53:30', 1.0, 2.0, 3.0, 4.0, 3.0);

You need to create this string dynamically (with real values) and use instead of INSERT_SQL.