MySQL Create Table

Creating a Table

To create a table in MySQL, use the “CREATE TABLE” statement.

Make sure you define the name of the database when you create the connection:

Example

Create a table named “customers”:

var mysql = require(‘mysql’);

var con = mysql.createConnection({
host: “localhost”,
user: “yourusername“,
password: “yourpassword“,
  database: “mydb”
});

con.connect(function(err) {
if (err) throw err;
console.log(“Connected!”);
var sql = “CREATE TABLE customers (name VARCHAR(255), address VARCHAR(255))”;
con.query(sql, function (err, result) {
if (err) throw err;
console.log(“Table created”);
});
});

Run example »

Save the code above in a file called “demo_create_table.js” and run the file:

Run “demo_create_table.js”

C:UsersYour Name>node demo_create_table.js

Which will give you this result:

Connected!
Table created


Primary Key

When creating a table, you should also create a column with a unique key for each record.

This can be done by defining a column as “INT AUTO_INCREMENT PRIMARY KEY” which will insert a unique number for each record. Starting at 1, and increased by one for each record.

Example

Create primary key when creating the table:

var mysql = require(‘mysql’);

var con = mysql.createConnection({
host: “localhost”,
user: “yourusername“,
password: “yourpassword“,
database: “mydb”
});

con.connect(function(err) {
if (err) throw err;
console.log(“Connected!”);
var sql = “CREATE TABLE customers (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), address VARCHAR(255))”;
con.query(sql, function (err, result) {
if (err) throw err;
console.log(“Table created”);
});
});

Run example »

If the table already exists, use the ALTER TABLE keyword:

Example

Create primary key on an existing table:

var mysql = require(‘mysql’);

var con = mysql.createConnection({
host: “localhost”,
user: “yourusername“,
password: “yourpassword“,
database: “mydb”
});

con.connect(function(err) {
if (err) throw err;
console.log(“Connected!”);
var sql = “ALTER TABLE customers ADD COLUMN id INT AUTO_INCREMENT PRIMARY KEY“;
con.query(sql, function (err, result) {
if (err) throw err;
console.log(“Table altered”);
});
});

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