SQL SELECT, DISTINCT, WHERE. Operators: AND, OR, ORDER BY. Taken from http://www.w3schools.com/sql/sql_select.asp

select.sql

--The SELECT statement is used to select data from a database.

--SQL SELECT Syntax:

SELECT column_name,column_name
FROM table_name;

--or:

SELECT * FROM table_name;

--SELECT Column Example

SELECT CustomerName,City FROM Customers;

--SELECT * Example

SELECT * FROM Customers;

--The SQL SELECT DISTINCT Statement
--The SELECT DISTINCT statement is used to return only distinct (different) values.

--SQL SELECT DISTINCT Syntax:

SELECT DISTINCT column_name,column_name
FROM table_name;

--SELECT DISTINCT Example

SELECT DISTINCT City FROM Customers;

--The SQL WHERE Clause 
--The WHERE clause is used to filter records.

--SQL WHERE Syntax
SELECT column_name,column_name
FROM table_name
WHERE column_name operator value;

--Example:

SELECT * FROM Customers
WHERE Country='Mexico';

--Text Fields vs. Numeric Fields
--SQL requires single quotes around text values (most database systems will also allow double quotes).

--However, numeric fields should not be enclosed in quotes:

--Example:

SELECT * FROM Customers
WHERE CustomerID=1;

--Operators in The WHERE Clause

/*
The following operators can be used in the WHERE clause:

Operator	Description

=       Equal
<>      Not equal. Note: In some versions of SQL this operator may be written as !=
>       Greater than
<       Less than
>=      Greater than or equal
<=      Less than or equal
BETWEEN Between an inclusive range
LIKE    Search for a pattern
IN      To specify multiple possible values for a column
*/


--SQL AND & OR Operators
--The AND & OR operators are used to filter records based on more than one condition.

--AND Example:

SELECT * FROM Customers
WHERE Country='Germany'
AND City='Berlin';

--OR Example:

SELECT * FROM Customers
WHERE City='Berlin'
OR City='München';

--Combining AND and OR Example:

SELECT * FROM Customers
WHERE Country='Germany'
AND (City='Berlin' OR City='München');

--ORDER BY
--The ORDER BY keyword is used to sort the result-set.

--SQL ORDER BY Syntax:

SELECT column_name, column_name
FROM table_name
ORDER BY column_name ASC|DESC, column_name ASC|DESC;

--Example:

SELECT * FROM Customers
ORDER BY Country;

--ORDER BY DESC Example:

SELECT * FROM Customers
ORDER BY Country DESC;

--ORDER BY Several Columns Examples:

SELECT * FROM Customers
ORDER BY Country, CustomerName;

SELECT * FROM Customers
ORDER BY Country ASC, CustomerName DESC;