This tutorial has some relevant info for many of the certifications out there. As far as real life knowledge, knowing the basic of DB and SQL allow you to better understand common attacks such as SQL Injection, Parameter Manipulation and others. If you are new the the world of Databases this could help quickly learn the basics. See the message below from Alex:
Hi, I am Alex Nordeen Editor at Guru99.
Our Goal is to provide Fun and Free Education for ALL.
I want to highlight that we recently created http://www.guru99.com/sql.html that took 190+ hours to create with beautifully, annotated screenshot, and it is very comprehensive.
The tutorial is created by a Google veteran and I have personally edited them.
The course covers • SQL Basics like Database Fundamentals, Design, • It also Covers SQL Basics Commands, Data Sorting, Regular Expressions & Wild Cards. • We also touch on advanced topics like SQL Functions used in PHP, Null value, Keyword, Sub-Queries in MySQL, and Creating an Application using MYSQL.