Reputation: 1838
The situation is: In one http GET request I need to select from one table the information I need and send to the client, and at the same time I need to retrieve the user IP and insert into a database. I'm using Node.js for this experiment.
The thing is: Is there a way to make the two actions together? Or do I have to connect and make two separate queries? Is there a way to render the page and do the other INSERT action in the background? What is the fastest option?
app.get('/', function({
connect.query("SELECT column1, column2 FROM table;", function(err, ...
render("index", ...);
});
connect.query("INSERT INTO table2 SET ip=11111111;");
});
Upvotes: 2
Views: 1521
Reputation: 39981
The procedure approach suggested by @skv is nice but you have to wait for the write before doing the read and eventually returning a result to the user.
I would argue for another approach.
This has several benefits
Upvotes: 2
Reputation: 14003
Well, I assume you're using this module https://github.com/felixge/node-mysql
The MySQL protocol is sequential, then, to execute paralell queries against mysql, you need multiple connections. You can use a Pool to manage the connections.(builtin in the module)
Example:
var mysql = require('mysql');
var pool = mysql.createPool({
host: 'example.org',
user: 'bob',
password: 'secret',
connectionLimit: 5 // maximum number of connections to create at once **10 by default**
});
app.get('/', function (req, res) {
// get a connection from the pool //async
pool.getConnection(function (err, connection) {
// Use the connection
connection.query('SELECT something FROM table1', function (err, rows) {
// Do somethig whith the mysql_response and end the client_response
res.render("index", {...
});
connection.release();
// Don't use the connection here, it has been closed.
});
});
//async
var userIp = req.connection.remoteAddress || req.headers['x-forwarded-for'] || null;
if (userIp) {
// get a connection from the pool again
pool.getConnection(function (err, connection) {
// Use the connection
connection.query('INSERT INTO table2 SET ip=?', [userIp], function (err, rows) {
// And done with the insert.
connection.release(); // Conn Close.
});
});
}
});
Upvotes: 1
Reputation: 1803
You can make a stored procedure do this
Basically these are two different operations, but doing it in stored procedures might give you the assurance that it will surely happen, you can pass the IP address as the parameter into the stored procedure, this will also avoid any worries of performance in the code for you as the db takes care of insert, please remember that any select that does not insert into a table or a variable will produce a result set for you to use, hope this helps.
DELIMITER $
CREATE PROCEDURE AddIPandReturnInfo
(
@IPAddress varchar(20)
)
BEGIN
INSERT INTO Yourtable (IPAddress);
SELECT * FROM Tablename;
END $
DELIMITER ;
Upvotes: 2