SQL

I've hit a wall in my SQL studies via the Khan Academy, and as such, I am engaging in additional studies prior to attempting to move forward.

Via a very limited, free SQL tutorial from Codecademy:

BACKGROUND

SQL, Structured Query Language, is a programming language designed to manage data stored in relational databases. SQL operates through simple, declarative statements. This keeps data accurate and secure, and it helps maintain the integrity of databases, regardless of size.

Here’s an appendix of commonly used commands.

COMMANDS

ALTER TABLE

ALTER TABLE table_name 
ADD column_name datatype;

ALTER TABLE lets you add columns to a table in a database.