Chapter 8 Connecting Web App to Database - Exercises

 

Chapter 8

Connecting Web App to Database

Fill in the blanks.

1.      The mysqli_fetch_row function is used to fetch the records returned by the query.

2.      The  mysqli_query function will execute the query with the help of the connection object.

3.      The mysqli_select_db function is used to connect the database.

4.      The DBMS concept was first implemented in 1950s.

5.       The Hierarchical DBMS employs the parent-child relationship of storing data.

Write T for True and F for False.

1.      The mysqli_connect function connects the web app to the MySQL server.              T

2.      The mysqli_select_db function sets the active connection with the database.           T

3.      MySQL is a popular RDBMS.                                                                                   T

4.      The objects to be stored in the database have different attributes.                            T

5.      Network DBMS supports one-to-many relationships.                                                F

Application based questions.

1.     Anil is creating a DBMS that will store details of the teachers and classes they are teaching. Suggest the kind of DBMS Anil should use.

Relational DBMS

2.     Akshay wants to fetch the records from a table named Teacher. He wants to create a query and execute it. Help Akshay to write the syntax for the same.

$con=mysqli_connect(“localhost”,”root”,””);

Mysqli_select_db($con,”Teacher_Database);

$query=”select * from Teacher where Teacher_ID=$T_ID”;

$data=mysqli_query($query);

$result=mysqli_query($con,$query);

$row=mysqli_fetch_row($result);

Answer the following questions.

1.     What is Database? Give examples.

Database is an organized collection of data.

For example: Attendance of students in attendance register.

2.     Differentiate between the Network and Relational DBMS.

Network DBMS usually results in complex database structure as it supports many-to-many relationship.

RDBMS supports tables to make the database relationship. RDBMS supports predefined data                 types.

3.     What is SQL? Name any two SQL-based DBMS software.

SQL stands for Structured Query Language.

It helps in establishing two-way communication between the web app and the DBMS.

Software based on SQL are MYSQL , Postgre SQL, MySQL Workbench, HeidiSQL, etc.

4.     What is the difference between mysqli_connect and mysqli_select_db function?

mysqli_connect function connects the app to MySQL Server.

mysqli_select_db function sets an active connection with the database.

5.     Write down the main steps in connecting the web app to the database to obtain result from a table.

Step 1: Creating a connection with the MySQL server.

Step 2: Creating a connection with the database.

Step 3: Creating an SQL query to fetch data from the table.

Step 4: Executing the query.

Step 5: Displaying query result.