how to add some extra field in registration form in wordpress?

i want to add some extra field in my registration form in wordpre开发者_开发技巧ss site how to add it.and made entry in database. hope some one help me.thanks

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I have used the plugin 'Cimy User extra fields' on several clients' sites and found that it does the job very well.

Last installed on a site within the last couple of months, so Wordpress 3 support is fine.