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SQL

SQL, or Structured Query Language, gives you the power to access and manipulate databases. A database is a structured set of information stored on a computer or server.

Sets of data are stores in tables. Tables consist of rows and columns.

Example

Here’s an example of a table called Students:

Students

StudentID	StudentName	StudentEmail	StudentPhone	City
1	Orlando	Orlando@aca.com	123-456-7891	Houston
2	James	James@aca.com	123-456-7891	San Antonio
3	Kelly	Kelly@aol.com	123-456-7891	Austin
4	Kari	Kari@aol.com	123-456-7891	Austin
5	Jose	Jose@aca.com	123-456-7891	Dallas

The following command selects all the data from the table called Students:

SELECT * FROM Students;

*** Important SQL Commands

• SELECT - retrieves a set of data from a table
• UPDATE - change an entry in a table
• DELETE - remove an entry from a table
• INSERT INTO - add data into a table
• CREATE DATABASE - create database
• CREATE TABLE - create a table
• DROP TABLE - delete table

To select the columns StudentName and StudentEmail from the Students table:

SELECT StudentName, StudentEmail FROM Students;

To select all the students who live in Austin from the Students table:

SELECT * FROM Students
WHERE City='Austin';

Assignment

Complete the SQL Zoo Tutorial to practice working with SQL. Please complete everything through the “SUM and COUNT” section, including the quiz for that section.

All the material about JOIN operations is optional.

More Practice

• W3Schools SQL tutorial
• MySQL Installer for Windows (free)
• MySQL Workbench for Windows (free)