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.PlayNextMute

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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

A new column salary is created in the table employee2.


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