Preparing to move I’m selling stuff on GumTree which is UK based clone of Craigslist offering similar functionality but with Ads Similarly to Craigslist GumTree is powered by MySQL but unlike craigslist it looks like they are shy in tuning their MySQL Full Text Search index configuration and setting proper ft_min_word_len value. Searching for Audi [...]
MySQL: Data Storage or Data Processing
I was thinking today of how people tend to use MySQL in modern applications and it stroke me in many cases MySQL is not used to process the data, at least not on the large scale – instead it is used for data storage and light duty data retrieval. Even in this case however the [...]
Read Buffers, mmap, malloc and MySQL Performance
Monty Taylor posted interesting investigation of the fact read_buffer_size variable affects connection speed. This is not something you would expect right ? me too. Not only global user data is expected to be cached on startup but even if it is not why would you do full table scan to fetch single user information ? [...]
Merge Tables Gotcha
I had the interesting customer case today which made me to do a bit research on the problem. You can create merge table over MyISAM tables which contain primary key and global uniqueness would not be enforced in this case, this is as far as most people will think about it. In fact however it [...]
Falcon Storage Engine Design Review
Now as new MySQL Storage engine – Falcon is public I can write down my thought about its design, which I previously should have kept private as I partially got them while working for MySQL. These thought base on my understanding, reading docs, speaking to Jim, Monty, Arjen and other people so I might miss [...]
Test Drive of Solid
Not so long ago Solid released solidDB for MySQL Beta 3 so I decided now is time to take a bit closer look on new transactional engine for MySQL. While my far goal is the performance and scalability testing before I wanted to look at basic transactional properties such as deadlock detection, select for update [...]
Why Index could refuse to work ?
Have you ever seen index which refused to be used even if there is every reason for it to work (from the glance view):
1 2 3 4 5 6 7 | mysql> explain select * from article where article_id=10; +----+-------------+---------+------+---------------+------+---------+------+-------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+---------+------+---------------+------+---------+------+-------+-------------+ | 1 | SIMPLE | article | ALL | PRIMARY | NULL | NULL | NULL | 93490 | Using where | +----+-------------+---------+------+---------------+------+---------+------+-------+-------------+ 1 row in set (0.00 sec) |
Why on the earth index would not be used you would think, even if MySQL is mentioning it in “possible keys” ? Should you try to force it ?

