ISAM tables are included in MySQL purely for legacy support. Their functionality has been entirely replaced by MyISAM tables, so they will not be examined in any detail here. They are scheduled to be removed from MySQL in version 5.0. The following code will create an ISAM table, should you want to for some reason: create table asset ( assetID int not null, description varchar(255) ) type=ISAM; ISAM tables offer fast but not transaction-safe storage. Most of what we will say about MyISAM tables holds true for ISAM tables, but the older ISAM tables have several limitations. Improvements offered by MyISAM include the following:
ISAM tables should be regarded as being deprecated. They still exist, but they should not be used for new development. If you have any existing ISAM tables, you should strongly consider converting them to MyISAM. It takes very little effort and offers significant advantages. |