In my experience with MySql MyIsam is really really fast on inserts and reads. On the other hand if you have many users hitting the database at the same time inserting and querying data - you will start to see the performance of MyIsam fall sharply.

MyIsam is good when:

• you have alot of writes and very few reads
• You have alot of reads and very few writes
• You have a blog. Most of the time only a few writes a day between posts and comments

MyIsam is bad when:

• You have alot of reads and writes happening at the same time

I have tested postgresql and it out performs mysql MyIsam when the database is getting hit hard with both reads and writes happening at the same time. Furthermore, MyIsam tends to get corrupted at least once a month when you have a high traffic website.

In my experience with MySQL, MyIsam is really really fast on inserts and reads. On the other hand, if you have many users hitting the database at the same time inserting and querying data, you will start to see the performance of MyIsam fall sharply.

MyIsam is good when:

• You have a lot of writes and very few reads
• You have a lot of reads and very few writes
• You have a blog. Most of the time only a few writes a day between posts and comments

MyIsam is bad when:

• You have a lot of reads and writes happening at the same time

I have tested PostGreSQL and it out performs MySQL MyIsam when the database is getting hit hard with both reads and writes happening at the same time. Furthermore, MyIsam tends to get corrupted at least once a month when you have a high traffic website.