Loïc Faugeron has a post on his site covering the concept of short identifiers and covering some of the common types along with some of the downsides of the use of each.

Sometimes resources can be identified by one of their attributes (a name, title, slug) and sometimes they can't (no name, or confidential name). In the later case, an ID needs to be artificially crafted.

Two of the popular strategies is to use either an auto incremental one or a universally unique one, however when it comes to share them publicly, both strategies present some drawbacks

He lists several different types including:

• Auto Incremental IDs
• Short IDs
• Hashes
• Alphabetical representation

In the end, the method he recommends is hashing the ID value and using the first few characters (much the way you can refer to commit hashes in the Git version control tool).

It seems like there's not a site out there anymore that doesn't use a database of some sort. Frankly, they're just a simple way to get the storage you need without the hassle of having to manage the resource yourself. It even comes with its own language to help query the data! Of course, with the good comes the bad, and this new article from IBM's developerWorks site about five common database mistakes.

If only there were one way to use databases correctly... You can create database design, database access, and the PHP business logic code that sits on top of it in any number of ways, and you often end up getting it wrong. This article illustrates five common problems in database design, in the PHP code that accesses databases, and how to fix these problems when you see them.

The problems they discuss are:

• Using MySQL directly
• Not using auto-increment functionality
• Using multiple databases
• Not using relations
• The n+1 pattern

Each of the items is discussed and explained with code samples for both the good and the bad side to make comparison easier. Knowing these issues before you develop your system definitely makes it easier, but they're still useful as a tool to fix things as well.

It seems like there's not a site out there anymore that doesn't use a database of some sort. Frankly, they're just a simple way to get the storage you need without the hassle of having to manage the resource yourself. It even comes with its own language to help query the data! Of course, with the good comes the bad, and this new article from IBM's developerWorks site about five common database mistakes.

If only there were one way to use databases correctly... You can create database design, database access, and the PHP business logic code that sits on top of it in any number of ways, and you often end up getting it wrong. This article illustrates five common problems in database design, in the PHP code that accesses databases, and how to fix these problems when you see them.

The problems they discuss are:

• Using MySQL directly
• Not using auto-increment functionality
• Using multiple databases
• Not using relations
• The n+1 pattern

Each of the items is discussed and explained with code samples for both the good and the bad side to make comparison easier. Knowing these issues before you develop your system definitely makes it easier, but they're still useful as a tool to fix things as well.