gem "meta_search"
http://metautonomo.us/2010/03/07/metasearch-object-based-searching-for-rails-3/
this is good
http://metautonomo.us/projects/metawhere/
Debug your SQL with debug_sql
The to_sql method is a handy way to show your query, but as I’ve written about before,
it has its shortcomings. When your query is going to eager load some
records and has conditions referencing the eager loaded tables,
ActiveRecord changes its generated query, but to_sql is none the wiser.
Enter debug_sql:
ruby-1.9.2-head > Article.includes(:comments).where(:comments => {:body => 'hey'}).to_sql
=> SELECT "articles".* FROM "articles" WHERE ("comments"."body" = 'hey')
#
# LIES!!!
#
ruby-1.9.2-head > Article.includes(:comments).where(:comments => {:body => 'hey'}).debug_sql
=> SELECT "articles"."id" AS t0_r0, "articles"."title" AS t0_r1,
"articles"."body" AS t0_r2, "articles"."created_at" AS t0_r3,
"articles"."updated_at" AS t0_r4, "articles"."lookup_id" AS t0_r5,
"comments"."id" AS t1_r0, "comments"."article_id" AS t1_r1,
"comments"."body" AS t1_r2, "comments"."created_at" AS t1_r3,
"comments"."updated_at" AS t1_r4
FROM "articles" LEFT OUTER JOIN "comments"
ON "comments"."article_id" = "articles"."id"
WHERE ("comments"."body" = 'hey')
# The (ugly) truth!
强大的Rails查询、搜索插件:SearchLogic
这个似乎更好this is a tutorialsearch logic不支持rails3https://github.com/railsdog/searchlogic.git上面这个好像是别人修改的版本,
问题insalllgem 'rd_searchlogic', :require => 'searchlogic', :git => 'git://github.com/railsdog/searchlogic.git'