JavaScript Set 7

Question 1

What does NPM stand for and what does it do?

Answer 1

Stands for Node.js package manager
It is the default package manager for Node.js runtime
It is the world’s largest software registry and is used by developers to share software

Question 2

What are DML statements?

Answer 2

Stands for data manipulation language. They are a subset of SQL used for managing data in a database

Question 3

What are the 4 main DML statements?

Answer 3

1. SELECT to retrieve data from a table
2. INSERT to put data in a table
3. UPDATE to update data in a table
4. DELETE to remove data from a table

Question 4

What are DDL statements?

Answer 4

Stands for data definition language. They are a subset of SQL used for defining and managing the structure of a database and its objects

Question 5

What are the 2 main DDL statements?

Answer 5

1. CREATE DATABASE
2. CREATE TABLE

Question 6

How can you connect to MySQL using node.js?

Answer 6

1. Install mysql package with npm
   npm install mysql
2. Include the mysql package in the JS code
   require(‘mysql’);
3. Create a mysql connection object
   var con = mysql.createConnection({host: “”, user: “”, password: “”});

Question 7

How can you create a database with the mysql package?

Answer 7

var con = mysql.createConnection({host: “”, user: “”, password: “”});
con.connect(function(err) {
con.query(create db statement,
callback function(err, result));
});

Question 8

How can you create a table with the mysql package?

Answer 8

var con = mysql.createConnection({host: “”, user: “”, password: “”, database:””});
con.connect(function(err) {
con.query(create table statement,
callback function(err, result));
});

Question 9

How can you insert a single record into a table with the mysql package?

Answer 9

var con = mysql.createConnection({host: “”, user: “”, password: “”, database: “”});
con.connect(function(err) {
var sql = “INSERT INTO table…”;
con.query(sql, callback function(err,
result));
});

Question 10

How can you insert multiple records into a table with the mysql package?

Answer 10

var con = mysql.createConnection({host: “”, user: “”, password: “”, database: “”});
con.connect(function(err) {
var sql = “INSERT INTO table
(columns) VALUES ?”
var values = [[record 1], [record 2],
…];
con.query(sql, [values], callback
function (err, result));
});

Question 11

How can you select data from a table with the mysql package?

Answer 11

var con = mysql.createConnection({host: “”, user: “”, password: “”, database: “”});
con.connect(function(err) {
var sql = “SELECT * FROM table”;
con.query(sql, callback function(err,
result, fields));
});

Question 12

How can you delete data from a table with the mysql package?

Answer 12

var con = mysql.createConnection({host: “”, user: “”, password: “”, database: “”});
con.connect(function(err) {
var sql = “DELETE FROM table
WHERE…”;
con.query(sql, callback function(err,
result, fields);
});

Question 13

How can you update data in a table with the mysql package?

Answer 13

var con = mysql.createConnection({host: “”, user: “”, password: “”, database: “”});
con.connect(function(err) {
var SQL = “UPDATE table SET
field=value WHERE condition”;
con.query(sql, function(err, result,
fields));
});