Node.js MySQL Create Table

CREATE TABLE command is used to create a table in MySQL. You must make it sure that you define the name of the database when you create the connection.

Example

For creating a table named “employees”.

Create a js file named employees.js having the following data in DBexample folder.

var mysql = require('mysql');  

var con = mysql.createConnection({  

host: "localhost",  

user: "root",  

password: "12345",  

database: "javatpoint"  

});  

con.connect(function(err) {  

if (err) throw err;  

console.log("Connected!");  

var sql = "CREATE TABLE employees (id INT, name VARCHAR(255), age INT(3), city VARCHAR(255))";  

con.query(sql, function (err, result) {  

if (err) throw err;  

console.log("Table created");  

});  

});  

    Now open command terminal and run the following command:

    Node employees.js  
    Node.js create table 1

    Verification

    To verify if the table is created or not, use the SHOW TABLES command.

    Node.js create table 2

    You can also check the structure of the table using DESC command:

    Node.js create table 3

    Create Table Having a Primary Key

    Create Primary Key in New Table:

    Let’s create a new table named “employee2” having id as primary key.

    Create a js file named employee2.js having the following data in DBexample folder.

    var mysql = require('mysql');  
    
    var con = mysql.createConnection({  
    
    host: "localhost",  
    
    user: "root",  
    
    password: "12345",  
    
    database: "javatpoint"  
    
    });  
    
    con.connect(function(err) {  
    
    if (err) throw err;  
    
    console.log("Connected!");  
    
    var sql = "CREATE TABLE employee2 (id INT PRIMARY KEY, name VARCHAR(255), age INT(3), city VARCHAR(255))";  
    
    con.query(sql, function (err, result) {  
    
    if (err) throw err;  
    
    console.log("Table created");  
    
    });  
    
    });

    Now open command terminal and run the following command:

    Node employee2.js  
    Node.js create table 4

    Verification

    To verify if the table is created or not, use the SHOW TABLES command.

    Node.js create table 5

    You can also check the structure of the table using DESC command to see that id is a primary key :

    Node.js create table 6

    Add columns in existing Table:

    ALTER TABLE statement is used to add a column in an existing table. Take the already created table “employee2” and use a new column salary.

    Replace the data of the “employee2” table with the following data:

    var mysql = require('mysql');  
    
    var con = mysql.createConnection({  
    
    host: "localhost",  
    
    user: "root",  
    
    password: "12345",  
    
    database: "javatpoint"  
    
    });  
    
    con.connect(function(err) {  
    
    if (err) throw err;  
    
    console.log("Connected!");  
    
    var sql = "ALTER TABLE employee2 ADD COLUMN salary INT(10)";  
    
    con.query(sql, function (err, result) {  
    
    if (err) throw err;  
    
    console.log("Table altered");  
    
    });  
    
    });  

      Now open command terminal and run the following command:

      Node employee2.js  
      Node.js create table 7

      Verification

      Node.js create table 8

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