7.1.2.1 Static (Fixed-length) Table Characteristics

This is the default format. It's used when the table contains no VARCHAR, BLOB, or TEXT columns.

This format is the simplest and most secure format. It is also the fastest of the on-disk formats. The speed comes from the easy way data can be found on disk. When looking up something with an index and static format it is very simple. Just multiply the row number by the row length.

Also, when scanning a table it is very easy to read a constant number of records with each disk read.

The security is evidenced if your computer crashes when writing to a fixed-size MyISAM file, in which case myisamchk can easily figure out where each row starts and ends. So it can usually reclaim all records except the partially written one. Note that in MySQL all indexes can always be reconstructed:

• All CHAR, NUMERIC, and DECIMAL columns are space-padded to the column width.
• Very quick.
• Easy to cache.
• Easy to reconstruct after a crash, because records are located in fixed positions.
• Doesn't have to be reorganised (with myisamchk) unless a huge number of records are deleted and you want to return free disk space to the operating system.
• Usually requires more disk space than dynamic tables.

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