SQL seems like a pretty efficient and fast way to retrieve large amount of
records from a database. It seem like using SQL doesn't require a lot of
code writing. I also think creating views is useful because it allows you
to customize data. You don't have to worry about computed values or column
names being formatted differently than the base table columns when you want
to display them.

*SQL stands for Structured Query Language
*RDBMS (Relational Database Management System) is the basis for SQL and for
 all modern database systems
*to build a web site that shows data from a database you need an RDBMS
 program, server-side scripting langauge (PHP, ASP, etc.), SQL ot get the
 data, HTML/CSS

*lets you access and manipulate databases. It can:
      -execute queries
      -retrieve data
      -insert/update/delete records
      -create new databases/tables in database
      -create stored procedures
      -create views
      -set permissions (on tables, procedures, and views)

*actions are done using SQL statements

*important commands (not case sensitive):
SELECT - extracts data from a database
UPDATE - updates data in a database
DELETE - deletes data from a database
INSERT INTO - inserts new data into a database
CREATE DATABASE - creates a new database
ALTER DATABASE - modifies a database
CREATE TABLE - creates a new table
ALTER TABLE - modifies a table
DROP TABLE - deletes a table
CREATE INDEX - creates an index (search key)
DROP INDEX - deletes an index

*a column may contain many duplicate values and sometimes you
 only want to list the different (distinct) values. The DISTINCT keyword
 can be used to return only distinct (different) values. It looks like
 this:

SELECT DISTINCT column_name,column_name
FROM table_name;

*WHERE clause used to extract only those records that fulfill a specified
 criterion. It looks like this:

SELECT column_name,column_name
FROM table_name
WHERE column_name operator value;

*to specify multiple values in  WHERE clause, us the IN operator. It looks
 like this:

SELECT column_name(s)
FROM table_name
WHERE column_name IN (value1,value2,...);