MySQL and mSQL

What MySQL and mSQL Lack

The word “lack” is chosen here in absence of a better term. As we noted earlier in the book, both MySQL and mSQL have consciously chosen to leave out features that will impact performance. In other words, for MySQL and mSQL, performance is the name of the game. Some mid-range users, however, may be willing to sacrifice a little performance for some other features. In order to understand what other mid-range databases offer, then, it helps to know the things that MySQL and mSQL have left out.

Note

MySQL intends to eventually include some of these features with the ability to turn them off if you do not want them. At the time of printing, we are aware that Monty wants to implement a stored procedure mechanism and subselects and perhaps even transactions.

Transactions

Transactions enable you to group multiple SQL statements together as one unit of work. By grouping statements together, you can be certain that no one else will see a partially changed database. You also know that if one of the statements fail, the entire unit of work fails. One way of visualizing transactions is as the intersection of a busy road. A single-threaded queuing system, such as mSQL, is like having a four-way stop at the intersection. Each car takes its turn, one at a time. If two cars are in a caravan through the intersection, they risk being split up at the stop sign.

A multithreaded locking system, such as MySQL, is more like having a traffic officer instead of stop signs. The traffic ...