node. JS (Connection MySQL)

SQL in the MySQL statement

Classification in SQL statements:

---DDL: (data define language) to define the columns (create,drop,alter,truncate)

---DML: (data manipulate language)-operation data row (insert Delete,update)

---DQL: (data Query Language)--querying (SELECT)

---DCL: (Data Control Language)--controlling user rights (Grant,revoke)

Using node. js to access the MySQL server requires the use of a third-party module--mysql module

1.---Create a connection to the database server

Const MySQL = require (' mysql ');

var con = mysql.createconnertion ({});

---Send SQL statements to the database server for execution

Con.query (' sql ... ', function (Err,result) {});

---close connection con.end ();

2.--Creating a connection pool

Const MySQL = require (' mysql ');

var pool = Mysql.createpool ({

Host: ' localhost ',

User: ' Root ',

Password: ",

Connectionlimit:10});

Pool.getconnection ((Err,con) =>{

Con.query (' sql:?,? [ x, Y], (err,result) =>{

Con.release ();

}}

node. JS (Connection MySQL)