mode 4 JDBC

Question 1

What is a Design Pattern

Answer 1

Opinionated

It is a solution to a common problem.

Question 2

What is the DAO design pattern?

Answer 2

Data Access Object

its a design pattern that allows us to serperate the application/business logic from the persistance layer

its how we separate our requirement logic / code and logic for our database

Question 3

What are the layers in the DAO design pattern?

Answer 3

> DAO Layer - directly accesses the database (using JDBC)
>Service Layer - directly acceses the DAO layer

What are layers??
packages! They will have their own packages

Question 4

What is the heirachy of full stack

Answer 4

talks to                                talks to                        talks to
Frontend   
     ||     ^
     V    ||
Backend Controller  
     ||     ^
     V    ||
Service Layer 
   ||     ^
     V    ||
DAO Layer
  ||     ^
  V    ||

Question 5

What is JDBC?

Answer 5

Java Database Connectivity
> JDBC is technology that allows java to connect to a database
> JDBC is modular. It doesnt connect to any specific DB it can connect to any DB as long as it has the driver

Question 6

What is needed for you to be able to connect to a database?

Answer 6

> url
> username
> password
> driver for the specific database

Question 7

Important classes/interfaces that JDBC uses

Answer 7

Important classes/interfaces that JDBC uses
	DriverManager (class)
	Connection (interface)
	Statement (interface)
		PreparedStatement(interface)
		CallableStatement(interface)
	ResultSet (interface)

Question 8

What are some common errors you may have in JDBC

Answer 8

“No suitable driver found”
the two common reasons wh you’ll see this are:
-you forgot to add the dependency to your gradle…in short, you don’t have a driver at all
-your url has a typo

Question 9

Does JDBC needs a SPECIFIC format for the driver manager?

Answer 9

JDBC needs a SPECIFIC format to the URL string so that the DriverManager

 * can understand which driver that you are using
 *  
 * For PostgreSQL, the URL format is:
 * url = jdbc:postrgesql://[endpoint]/[databasename]