By using flowing query, you can easily convert wordpress database from any character set and collate to utf-8 character set and unicode_ci collate :
ALTER TABLE `wp_options` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_postmeta` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_posts` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_ratings` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_terms` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_usermeta` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_users` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_term_relationships` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_term_taxonomy` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;
Happy blogging !
Better solution
ALTER TABLE `wp_comments` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_links` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_options` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_postmeta` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_posts` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_ratings` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_terms` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_usermeta` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_users` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_term_relationships` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
ALTER TABLE `wp_term_taxonomy` CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
Comment by doqkhanh — April 10, 2009 @ 9:18 AM