如何通过导轨中的关联进行搜索4

Question

我想要获取所有主题名称将与搜索关键字匹配的配置文件。现在我正在加载所有配置文件。我需要知道我该如何实现它。任何帮助深表感谢。

Profile.rb

has_many :categorizations 
has_many :subjects, through: :categorizations 

subject.rb中

has_many :categorizations 
has_many :profiles, through: :categorizations 

Categorization.rb

belongs_to :profile 
belongs_to :subject 

意见/搜索/ index.html.erb

# search form 
<%= form_tag search_index_path, :method => 'get' do %> 
    <%= text_field_tag :search, params[:search] %> 
    <%= submit_tag "search", :name => nil %> 
<% end %> 

# search results 
<% @profiles.each do |profile| %> 
    <%= profile.name %> 
<% end %> 

search_controller.rb

def index 
    @profiles = Profile.with_translations('en').all 
end 

Answer 1

需要补充的是使用Rails的想法full text searching。如果你执行搜索，你需要知道，你实际在您的数据库，根据不同的SQL引擎，它是不同的全文“搜索”查询您使用

---

MYSQL全文搜索

LIKE %{search}%机制是MYSQL的非常基本的全文搜索功能，并且基本上在您的数据库中查找整个记录内的目标查询。这意味着，如果您的查询是这样的：

SELECT * FROM `products` WHERE `name` LIKE '%alligator%' 

MYSQL将基本贯穿整个“名”的记录查找任何引用到您的查询。结果将取决于您的记录是否在其任何部分都有“鳄鱼”一词。 This reference解释了更多关于这

---

PostgreSQL的全文搜索

我写这篇文章是因为PSQL实际做法与此不同，因此，你已经提供查询将只限于MySQL工作的原因。PSQL有很多不同的功能来处理全文搜索，但由于我们使用Heroku的，我们成功地使用Textacular gem把一切工作正常

这里有some ways PSQL handles full text searching：

Full text searching in PostgreSQL is based on the match operator @@, which returns true if a tsvector (document) matches a tsquery (query). It doesn't matter which data type is written first:

SELECT 'a fat cat sat on a mat and ate a fat rat'::tsvector @@ 'cat & 
rat'::tsquery; ?column? 
---------- t 

SELECT 'fat & cow'::tsquery @@ 'a fat cat sat on a mat and ate a fat 
rat'::tsvector; ?column? 
---------- f 

As the above example suggests, a tsquery is not just raw text, any more than a tsvector > is. A tsquery contains search terms, which must be already-normalized lexemes, and may combine multiple terms using AND, OR, and NOT operators. (For details see Section 8.11.) There are functions to_tsquery and plainto_tsquery that are helpful in converting user-written text into a proper tsquery, for example by normalizing words appearing in the text. Similarly, to_tsvector is used to parse and normalize a document string. So in practice a text search match would look more like this:

SELECT to_tsvector('fat cats ate fat rats') @@ to_tsquery('fat & rat'); ?column? 
---------- t Observe that this match would not succeed if written as 

SELECT 'fat cats ate fat rats'::tsvector @@ to_tsquery('fat & rat'); ?column? ---------- f

---

全文搜索软件

全文搜索在数据库中本质上相当昂贵，特别是如果您有大量数据要搜索时。这就是为什么像sunspot solr或sphinx解决方案存在 - 提供了一种既指标&搜索数据，你有

如果您的应用程序变得非常流行，你不妨投入到全文检索系统之一，如these demonstrated by Heroku：

Answer 2

@profiles = Subject.where("name LIKE ?", "%#{params[:search]}%").map(&:profiles) 

Answer 3

检查，如果这个工程。

@profiles = Profile.joins(:subjects).where("subject.name like '%?%'",params[:search])