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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:
Create a table named "customers":
let mysql = require('mysql');
let con = mysql.createConnection({
host: "localhost", user: "yourusername ", password: " yourpassword ", database: "mydb"
});
con.connect(function(err) {
if (err) throw err;
console.log("Connected!");
let sql = "
CREATE TABLE customers (name VARCHAR(255), address VARCHAR(255)
)";
con.query(sql, function (err, result) {
if (err)
throw err;
console.log("Table created");
});
});
Save the code above in a file called "demo_create_table.js" and run the file:
Run "demo_create_table.js"C:\Users\
>node demo_create_table.js Which will give you this result: Connected!
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.
Create primary key when creating the table:
let mysql = require('mysql');
let con = mysql.createConnection({
host: "localhost", user: "yourusername ", password: " yourpassword ", database: "mydb"
});
con.connect(function(err) {
if (err) throw err;
console.log("Connected!");
let 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");
});
});If the table already exists, use the ALTER TABLE keyword:
Create primary key on an existing table:
let mysql = require('mysql');
let con = mysql.createConnection({
host: "localhost", user: "yourusername ", password: " yourpassword ", database: "mydb"
});
con.connect(function(err) {
if (err) throw err;
console.log("Connected!");
let sql = "
ALTER TABLE customers ADD COLUMN id INT AUTO_INCREMENT";
con.query(sql, function (err, result) {
if (err)
throw err;
console.log("Table altered");
});
});