Slide 14.21: Pros and cons of the JOIN clause

Slide 14.20: The FULL (OUTER) JOIN clause
Slide 14.22: A weakness of SQL: Too many equivalent forms
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Pros and Cons of the JOIN Clause

The two queries below are the same:

Pre-ANSI-92 SQL:

SELECT * FROM table_1, table_2
  WHERE table_1.column = table_2.column

ANSI-92 SQL:

SELECT * FROM table_1 JOIN table_2
  ON table_1.column = table_2.column

The main reason to use ANSI-92 syntax is because ANSI-89 does not have any OUTER JOIN (LEFT, RIGHT, FULL) support. The ANSI-92 syntax is recommended to be used:

The use of the JOIN clause separates the relationship logic from the filter logic (the WHERE clause) and is thus cleaner and easier to understand.

It is good practice as most developers and DBAs use ANSI-92 nowadays and you should follow the standard.

Demonstration
Below is an SQL test area from W3Schools, which uses the well-known Northwind sample database. The tables here are for read only because of the problem of embedding the scripts. For a fully working example, check this by using Chrome.

Result:

The Database includes:

Tablename	Record
Customers	91
Categories	8
Employees	10
OrderDetails	518
Orders	196
Products	77
Shippers	3
Suppliers	29

W3C WebSQL

WebSQL Browser Support