Are there any published coding style guidelines for SQL?

Question

Often I will end up with very complex SQL statements and I wondered if there was style guideline out there that dictates a common way of laying various aspects of a query out.

I am look for something descriptive along the lines of Python's PEP8 or Zend Frameworks guidelines and not code by example.

Most of my queries are written for MySQL.

So do you know of a universal style guide? Perhaps you have written one yourself. Please share your guidelines.

Answer 1

Since asking this question I have written a public SQL style guide that is compatible with Joe Celko's SQL Programming Style book under the Creative Commons Attribution-ShareAlike licence.

It is available over at www.sqlstyle.guide or as markdown directly from the GitHub repo.

Answer 2

Here are some SQL programming guidelines and best practices we collected:

• Do not use SELECT * in your queries.
• Always use table aliases when your SQL statement involves more than one source.
• Use the more readable ANSI-Standard Join clauses instead of the old style joins.
• Do not use column numbers in the ORDER BY clause.
• Always use a column list in your INSERT statements.
• Don't ever use double quotes in your T-SQL code.
• Do not prefix your stored procedure names with “sp_”.
• Always use a SQL formatter to format your SQL like Instant SQL Formatter (free and online)

You can check detailed explanation of those best practices in this blog post.