在Rails中使用Filterrific来搜索活动记录关联

Question

我有一个教师模型和一个学生模型（教师has_many学生）。希望使用Filterrific通过他们的学生的名字搜索老师。

filterrific的默认功能是根据SQL查询向教师表搜索教师。

我想知道如何根据他们的关联表来搜索教师。这里是teacher.rb的SQL代码：

scope :search_query, lambda { |query| 
    return nil if query.blank? 
    # condition query, parse into individual keywords 
    terms = query.downcase.split(/\s+/) 
    # replace "*" with "%" for wildcard searches, 
    # append '%', remove duplicate '%'s 
    terms = terms.map { |e| 
     (e.gsub('*', '%') + '%').gsub(/%+/, '%') 
    } 
    # configure number of OR conditions for provision 
    # of interpolation arguments. Adjust this if you 
    # change the number of OR conditions. 
    num_or_conditions = 3 
    where(
     terms.map { 
     or_clauses = [ 
      "LOWER(teachers.first_name) LIKE ?", 
      "LOWER(teachers.last_name) LIKE ?", 
      "LOWER(teachers.email) LIKE ?" 
     ].join(' OR ') 
     "(#{ or_clauses })" 
     }.join(' AND '), 
     *terms.map { |e| [e] * num_or_conditions }.flatten 
    ) 
    } 

Answer 1

我把示例代码从一个场景，我用includes，而不是joins，因为我需要一个右外连接。在这种情况下，我必须让Rails知道我正在引用学生表。

我不确定您是否确实需要references部分与joins。尝试一下，我会很好奇，知道它是否有效。

scope :search_query_by_students, lambda { |query| 
    return nil if query.blank? 
    # condition query, parse into individual keywords 
    terms = query.downcase.split(/\s+/) 
    # replace "*" with "%" for wildcard searches, 
    # append '%', remove duplicate '%'s 
    terms = terms.map { |e| 
    (e.gsub('*', '%') + '%').gsub(/%+/, '%') 
    } 
    # configure number of OR conditions for provision 
    # of interpolation arguments. Adjust this if you 
    # change the number of OR conditions. 
    num_or_conditions = 3 
    where(
    terms.map { 
     or_clauses = [ 
     "LOWER(students.first_name) LIKE ?", 
     "LOWER(students.last_name) LIKE ?", 
     "LOWER(students.email) LIKE ?" 
     ].join(' OR ') 
     "(#{ or_clauses })" 
    }.join(' AND '), 
    *terms.map { |e| [e] * num_or_conditions }.flatten 
).joins(:students).references(:students) 
}