HyperDB is a replacement for the standard wpdb class which adds the ability to use multiple databases. HyperDB supports partition of data as well as replication.
Partitioning of Data
This involves moving different tables or different parts of the database into different databases, and normally on different servers. This allows you to scale an application by adding more database servers, so your data could be spread across several servers.
HyperDB allows you to specify which data resides on which servers.
Replication involves having one database server act as the master (the central copy of all data) and other servers act as slaves (each with a copy of the data). All the database writes must go to the master server, but database reads can be sent to slave servers, thus spreading the load amongst multiple servers.
HyperDB allows you to split database writes and reads and assign each to an array of servers.
HyperDB allows multiple servers to be configured and multiple routes to servers. If the first server can’t be accessed the second server is tried, if that’s down the third server, and so on. This allows for failover from internal nics to public nics to remote datacentres, etc.
“”In the NoSQL space this kind of real-world data is still a bit vague,” writes Todd Hoff at High Scalability. “When asked, vendors tend to give very general answers like NoSQL is good for BigData or key-value access. What does that mean for for the developer in the trenches faced with the task of solving a specific problem and there are a dozen confusing choices and no obvious winner? Not a lot.””
” InfoQ has released a video of Twitter’s Kevin Weil speaking at Strange Loop earlier this year on how the company uses NoSQL. Weil is quick to point out that Twitter is heavily dependent on MySQL. However, Twitter does employ NoSQL solutions for many purposes for which MySQL isn’t ideal. According to Weil, Twitter users generate 12 terrabytes of data a day – about four petabytes per year. And that amount is multiplying every year. Read on for our notes on Weil’s talk.”
Et si MySQL vivait de nouveau de ses propres ailes… sous un autre nom ? C'est en quelque sorte l'ambition de Michael Widenius, alias Monty, le développeur originel de la base de données Open Source et fondateur de MySQL AB. Monty Widenius promeut aujourd'hui MariaDB, un clone de MySQL, ou plutôt « la même base, avec plus de fonctions et moins de bugs », nous a-t-il confié.
The Drizzle project is building a database optimized for Cloud and Net applications. It is being designed for massive concurrency on modern multi-cpu/core architecture. The code is originally derived from MySQL.
Pendant son keynote, Karen a annoncée, la sortie de MySQL 5.4, la solution attendu depuis des mois aux problèmes de montée en charge de MySQL.