mysql, creating index

[matjaz]

hello,

one of my database tables size had:

• 350MB
• 1,920,338 records
• MyISAM

in phpmyadmin i added another field to the table + index on this field. my action resulted in terrible mysql performance which lasted for 10 minutes [server is good, not bad at all]. mysql processes went to sky, whole machine was slow, i was unable to do a regular select...

my question to db experts is: once my table grows to such size [300+ MB, yes i want to keep all the data in one table, rather than move old data somewhere else] is there a better wayto add a field + creat an index? database & website must be running of course...

thanks

[JDcrack]

Does this help?

http://www.mysql.com/doc/en/Table_size.html

[matjaz]

it doesnt answer my question really... it tells max size but i am already having problems with at 300MB.