Book Image

The SQL Workshop

By : Frank Solomon, Prashanth Jayaram, Awni Al Saqqa
Book Image

The SQL Workshop

By: Frank Solomon, Prashanth Jayaram, Awni Al Saqqa

Overview of this book

Many software applications are backed by powerful relational database systems, meaning that the skills to be able to maintain a SQL database and reliably retrieve data are in high demand. With its simple syntax and effective data manipulation capabilities, SQL enables you to manage relational databases with ease. The SQL Workshop will help you progress from basic to advanced-level SQL queries in order to create and manage databases successfully. This Workshop begins with an introduction to basic CRUD commands and gives you an overview of the different data types in SQL. You'll use commands for narrowing down the search results within a database and learn about data retrieval from single and multiple tables in a single query. As you advance, you'll use aggregate functions to perform calculations on a set of values, and implement process automation using stored procedures, functions, and triggers. Finally, you'll secure your database against potential threats and use access control to keep your data safe. Throughout this Workshop, you'll use your skills on a realistic database for an online shop, preparing you for solving data problems in the real world. By the end of this book, you'll have built the knowledge, skills and confidence to creatively solve real-world data problems with SQL.
Table of Contents (13 chapters)

11. Advanced SQL

Activity 11.01: Implementing the LIKE Operator

Solution:

  1. Enter the following query:
    SELECT O.OrderID, O.CustomerID, O.OrderNumber, O.OrderDate,       O.ShipmentDate, O.OrderStatus, O.Notes
    FROM   Orders O
    WHERE  O.Notes LIKE '%CUST%' AND O.ShipmentDate > '01051995'

    We have set two filter conditions. Only when both are satisfied will the product be displayed.

  2. On execution of the query, your result will look similar to the following:

Figure 11.22: Customer notes post May 5, 1995

Notice that there are only three orders that have an order date post May 1, 1995 and have CUST as part of the Notes section.

Activity 11.02: Using Transactions

Solution:

  1. Execute the following code to verify the existence of the specific OrderItems rows:
    USE PACKT_ONLINE_SHOP; 
     
    SELECT    OrderItemID, OrderID, ProductID, Quantity,
              UnitPrice, Discount, Notes
    FROM     OrderItems
    WHERE    OrderID = 5; 

    The output...