Ruby on rails 为什么这个Ruby squel（PostgreSQL）调用返回nil，而它显然不是？
我有一个搜索页面，允许用户根据GPA和sport stats等标准搜索运动员。当只使用一个搜索筛选器时，PostgreSQL将返回正确答案。当使用多个搜索筛选器时，只有在两个搜索筛选器中使用相同的统计信息时，它才会起作用。例如，如果我搜索GPA>3且GPA==4，它将返回相应的运动员。如果我在同一名运动员身上执行GPA>3和ACT>20，这两项都是真的，那么它不会返回空数组 以下是@conditions在代码中转换为数组而不是散列的内容，以便循环可以迭代，供整个页面参考，但您可以了解要点：Ruby on rails 为什么这个Ruby squel（PostgreSQL）调用返回nil，而它显然不是？,ruby-on-rails,ruby,postgresql,squeel,Ruby On Rails,Ruby,Postgresql,Squeel,我有一个搜索页面，允许用户根据GPA和sport stats等标准搜索运动员。当只使用一个搜索筛选器时，PostgreSQL将返回正确答案。当使用多个搜索筛选器时，只有在两个搜索筛选器中使用相同的统计信息时，它才会起作用。例如，如果我搜索GPA>3且GPA==4，它将返回相应的运动员。如果我在同一名运动员身上执行GPA>3和ACT>20，这两项都是真的，那么它不会返回空数组 以下是@conditions在代码中转换为数组而不是散列的内容，以便循环可以迭代，供整个页面参考，但您可以了解要点： {
{
"0"=>{"category"=>"1", "stat_type_id"=>"22", "predicate"=>"Greater Than",
"q"=>"2", "type"=>"stat"},
"1"=>{"category"=>"1", "stat_type_id"=>"2",
"predicate"=>"Greater Than", "q"=>"10", "type"=>"stat"}
}
def query
relation = Athlete.listed.for_sport( self.sport )
return relation if @conditions.blank?
@conditions = @conditions.map { |k, v| v } if @conditions.is_a?(Hash)
debugger
@conditions.each do |condition|
case condition[:type]
when "stat"
if !condition[:q].eql?("")
relation = case condition[:predicate]
when /less than/i
relation.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.lt (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
when /greater than/i
relation.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.gt (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
when /equal to/i
relation.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.eq (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
when /not equal to/i
relation.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.not_eq (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
end
end
when "academic"
relation
when "social"
relation
end
end
relation
end
SELECT "users"."id" AS t0_r0,
"users"."name" AS t0_r1,
"users"."first_name" AS t0_r2,
"users"."last_name" AS t0_r3,
"users"."facebook_id" AS t0_r4,
"users"."access_token" AS t0_r5,
"users"."birthday" AS t0_r6,
"users"."gender" AS t0_r7,
"users"."device_token" AS t0_r8,
"users"."current_city" AS t0_r9,
"users"."hometown" AS t0_r10,
"users"."relationship_status" AS t0_r11,
"users"."avatar_file_name" AS t0_r12,
"users"."avatar_content_type" AS t0_r13,
"users"."avatar_file_size" AS t0_r14,
"users"."avatar_updated_at" AS t0_r15,
"users"."email" AS t0_r16,
"users"."encrypted_password" AS t0_r17,
"users"."reset_password_token" AS t0_r18,
"users"."reset_password_sent_at" AS t0_r19,
"users"."remember_created_at" AS t0_r20,
"users"."sign_in_count" AS t0_r21,
"users"."current_sign_in_at" AS t0_r22,
"users"."last_sign_in_at" AS t0_r23,
"users"."current_sign_in_ip" AS t0_r24,
"users"."last_sign_in_ip" AS t0_r25,
"users"."authentication_token" AS t0_r26,
"users"."created_at" AS t0_r27,
"users"."updated_at" AS t0_r28,
"users"."time_zone" AS t0_r29,
"users"."username" AS t0_r30,
"users"."middle_name" AS t0_r31,
"users"."primary_sport_id" AS t0_r32,
"users"."state" AS t0_r33,
"users"."high_school" AS t0_r34,
"users"."phone" AS t0_r35,
"users"."user_type_id" AS t0_r36,
"users"."agreed_to_terms_and_conditions" AS t0_r37,
"users"."agreed_to_information_integrity" AS t0_r38,
"users"."agreed_to_content_responsibility" AS t0_r39,
"users"."account_type_id" AS t0_r40,
"users"."social_score" AS t0_r41,
"users"."recruit_year" AS t0_r42,
"users"."college_major" AS t0_r43,
"users"."secondary_sport_id" AS t0_r44,
"users"."handedness" AS t0_r45,
"users"."checkdin_id" AS t0_r46,
"users"."allow_twitter_sync" AS t0_r47,
"users"."allow_facebook_sync" AS t0_r48,
"users"."head_coach" AS t0_r49,
"users"."head_coach_email" AS t0_r50,
"users"."has_recruited_others" AS t0_r51,
"users"."customer_id" AS t0_r52,
"users"."last_4_digits" AS t0_r53,
"users"."removed_from_listing" AS t0_r54,
"users"."slug" AS t0_r55,
"users"."college_minor" AS t0_r56,
"users"."type" AS t0_r57,
"users"."billing_expiration_month" AS t0_r58,
"users"."billing_expiration_year" AS t0_r59,
"users"."billing_name" AS t0_r60,
"users"."billing_address" AS t0_r61,
"users"."billing_city" AS t0_r62,
"users"."billing_state" AS t0_r63,
"users"."billing_zip" AS t0_r64,
"users"."college_id" AS t0_r65,
"users"."agreed_to_age_requirements" AS t0_r66,
"users"."primary_sport_primary_position_id" AS t0_r67,
"users"."secondary_sport_primary_position_id" AS t0_r68,
"users"."recruit_status_id" AS t0_r69,
"users"."active_flag" AS t0_r70,
"users"."public" AS t0_r71,
"invitations"."id" AS t1_r0,
"invitations"."sender_id" AS t1_r1,
"invitations"."role_id" AS t1_r2,
"invitations"."to" AS t1_r3,
"invitations"."accepted_at" AS t1_r4,
"invitations"."token" AS t1_r5,
"invitations"."created_at" AS t1_r6,
"invitations"."updated_at" AS t1_r7,
"invitations"."current_state" AS t1_r8,
"invitations"."requester_id" AS t1_r9,
"invitations"."user_type" AS t1_r10,
"invitations"."type" AS t1_r11
FROM "users"
INNER JOIN "stats"
ON "stats"."athlete_id" = "users"."id"
LEFT OUTER JOIN "invitations"
ON "invitations"."requester_id" = "users"."id"
WHERE "users"."removed_from_listing" = 'f'
AND "users"."type" IN ( 'Athlete' )
AND (( "invitations"."current_state" IN ( 'accepted' )
OR "invitations"."current_state" IS NULL ))
AND ( users.primary_sport_id = 13
OR users.secondary_sport_id = 13 )
AND (( "stats"."stat_type_id" = 22
AND "stats"."value" > '2.0' ))
SELECT "users"."id" AS t0_r0,
"users"."name" AS t0_r1,
"users"."first_name" AS t0_r2,
"users"."last_name" AS t0_r3,
"users"."facebook_id" AS t0_r4,
"users"."access_token" AS t0_r5,
"users"."birthday" AS t0_r6,
"users"."gender" AS t0_r7,
"users"."device_token" AS t0_r8,
"users"."current_city" AS t0_r9,
"users"."hometown" AS t0_r10,
"users"."relationship_status" AS t0_r11,
"users"."avatar_file_name" AS t0_r12,
"users"."avatar_content_type" AS t0_r13,
"users"."avatar_file_size" AS t0_r14,
"users"."avatar_updated_at" AS t0_r15,
"users"."email" AS t0_r16,
"users"."encrypted_password" AS t0_r17,
"users"."reset_password_token" AS t0_r18,
"users"."reset_password_sent_at" AS t0_r19,
"users"."remember_created_at" AS t0_r20,
"users"."sign_in_count" AS t0_r21,
"users"."current_sign_in_at" AS t0_r22,
"users"."last_sign_in_at" AS t0_r23,
"users"."current_sign_in_ip" AS t0_r24,
"users"."last_sign_in_ip" AS t0_r25,
"users"."authentication_token" AS t0_r26,
"users"."created_at" AS t0_r27,
"users"."updated_at" AS t0_r28,
"users"."time_zone" AS t0_r29,
"users"."username" AS t0_r30,
"users"."middle_name" AS t0_r31,
"users"."primary_sport_id" AS t0_r32,
"users"."state" AS t0_r33,
"users"."high_school" AS t0_r34,
"users"."phone" AS t0_r35,
"users"."user_type_id" AS t0_r36,
"users"."agreed_to_terms_and_conditions" AS t0_r37,
"users"."agreed_to_information_integrity" AS t0_r38,
"users"."agreed_to_content_responsibility" AS t0_r39,
"users"."account_type_id" AS t0_r40,
"users"."social_score" AS t0_r41,
"users"."recruit_year" AS t0_r42,
"users"."college_major" AS t0_r43,
"users"."secondary_sport_id" AS t0_r44,
"users"."handedness" AS t0_r45,
"users"."checkdin_id" AS t0_r46,
"users"."allow_twitter_sync" AS t0_r47,
"users"."allow_facebook_sync" AS t0_r48,
"users"."head_coach" AS t0_r49,
"users"."head_coach_email" AS t0_r50,
"users"."has_recruited_others" AS t0_r51,
"users"."customer_id" AS t0_r52,
"users"."last_4_digits" AS t0_r53,
"users"."removed_from_listing" AS t0_r54,
"users"."slug" AS t0_r55,
"users"."college_minor" AS t0_r56,
"users"."type" AS t0_r57,
"users"."billing_expiration_month" AS t0_r58,
"users"."billing_expiration_year" AS t0_r59,
"users"."billing_name" AS t0_r60,
"users"."billing_address" AS t0_r61,
"users"."billing_city" AS t0_r62,
"users"."billing_state" AS t0_r63,
"users"."billing_zip" AS t0_r64,
"users"."college_id" AS t0_r65,
"users"."agreed_to_age_requirements" AS t0_r66,
"users"."primary_sport_primary_position_id" AS t0_r67,
"users"."secondary_sport_primary_position_id" AS t0_r68,
"users"."recruit_status_id" AS t0_r69,
"users"."active_flag" AS t0_r70,
"users"."public" AS t0_r71,
"invitations"."id" AS t1_r0,
"invitations"."sender_id" AS t1_r1,
"invitations"."role_id" AS t1_r2,
"invitations"."to" AS t1_r3,
"invitations"."accepted_at" AS t1_r4,
"invitations"."token" AS t1_r5,
"invitations"."created_at" AS t1_r6,
"invitations"."updated_at" AS t1_r7,
"invitations"."current_state" AS t1_r8,
"invitations"."requester_id" AS t1_r9,
"invitations"."user_type" AS t1_r10,
"invitations"."type" AS t1_r11
FROM "users"
INNER JOIN "stats"
ON "stats"."athlete_id" = "users"."id"
LEFT OUTER JOIN "invitations"
ON "invitations"."requester_id" = "users"."id"
WHERE "users"."removed_from_listing" = 'f'
AND "users"."type" IN ( 'Athlete' )
AND (( "invitations"."current_state" IN ( 'accepted' )
OR "invitations"."current_state" IS NULL ))
AND ( users.primary_sport_id = 13
OR users.secondary_sport_id = 13 )
AND (( "stats"."stat_type_id" = 22
AND "stats"."value" > '2.0' ))
AND (( "stats"."stat_type_id" = 2
AND "stats"."value" > '10' ))
def query
athletes = Athlete.listed.for_sport( self.sport )
relation = athletes
return relation if @conditions.blank?
@conditions = @conditions.map { |k, v| v } if @conditions.is_a?(Hash)
@conditions.each do |condition|
case condition[:type]
when "stat"
if !condition[:q].eql?("")
relation = case condition[:predicate]
when /less than/i
athletes.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.lt (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
when /greater than/i
athletes.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.gt (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
when /equal to/i
athletes.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.eq (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
when /not equal to/i
athletes.joins{stats}.where{(stats.stat_type_id.eq condition[:stat_type_id]) & (stats.value.not_eq (StatType.where(:id => condition[:stat_type_id]).first.display_as_decimal == true ? condition[:q].to_f.to_s : condition[:q].to_i.to_s))}
end
end
when "academic"
relation
when "social"
relation
end
end
relation
end
第二个查询有一个WHERE子句，其结尾如下：
AND (( "stats"."stat_type_id" = 22
AND "stats"."value" > '2.0' ))
AND (( "stats"."stat_type_id" = 2
AND "stats"."value" > '10' ))
INNER JOIN "stats"
ON "stats"."athlete_id" = "users"."id"
INNER JOIN "stats" AS s2
ON "s2"."athlete_id" = "users"."id"
(...)
AND (( "stats"."stat_type_id" = 22
AND "stats"."value" > '2.0' ))
AND (( "s2"."stat_type_id" = 2
AND "s2"."value" > '10' ))
SELECT athlete_id
FROM stats
WHERE
( "stats"."stat_type_id" = 22
AND "stats"."value" > '2.0' )
OR ( "s2"."stat_type_id" = 2
AND "s2"."value" > '10' )
GROUP BY athlete_id
HAVING COUNT(*)=<the number of parameters you want to filter by>
这将返回所有符合条件的运动员，以便将其与其他表连接起来。这些呈现的查询实在太长，无法读取。他们需要更好的格式。我想一个mod为我格式化了它，非常感谢！我在做这件事时遇到了一些问题。嗯，我理解Jakub Kania的问题，我只是不确定在我的循环中我必须做些什么才能让它起作用。有什么建议吗？谢谢请记住，它仍然需要以这样一种方式运行，即两个过滤器都必须为true才能返回运动员，它不应该返回过滤器1为true的所有运动员和过滤器2为true的所有运动员true@Robokid两次加入同一个表是一种方法。它也可以通过子查询来完成，但这会过于复杂。查看我的代码，我仍然不确定如何完成。我遇到的问题是，我的页面允许技术上无限的过滤器，就像用户希望通过“添加过滤器”按钮添加一样多，因此循环不止两次，它需要能够根据需要多次加入，而不会出现此问题。@Robokid我使用子查询解决方案进行了更新，这样对你来说很容易。非常感谢。我的问题是试图在squel中重写上面的内容，因为它没有别名或其他任何方法。