我正在使用grouped_option_select和辅助函数来为select的每一行提供标签，提供包含的数据。这导致了N + 1个查询，而且我不知道如何解决这个问题＆＃39; rails方式＆＃39;。
提前致谢。
模特：
class FbrlCode < ActiveRecord::Base
nilify_blanks
has_many :positions
has_many :people, through: :positions
belongs_to :brl_family
has_one :labor_category, :through => :brl_family
has_one :company, :through => :labor_category
validates :fbrl_code, :brl_family, presence: true
validates :fbrl_code, uniqueness: {case_sensitive: false}
validates_associated :brl_family
def fbrl_code_with_info
"#{fbrl_code} : #{brl_family.brl_family} : #{labor_category.labor_category}"
end
end
以下是相关的groups_collection_select：
<%= f.label :fbrl_code %>
<%= grouped_collection_select( :position, :fbrl_code_id, @companies, :fbrl_codes, :company_name, :id, :fbrl_code_with_info , { :prompt => 'Select FBRL Code', :multiple => false } ) %><br>
控制器中的急切加载
@companies = Company.includes(:labor_categories).includes(:brl_families).includes(:fbrl_codes).includes(:positions).distinct
rails服务器的输出：
Started GET "/positions/new" for 127.0.0.1 at 2015-06-08 14:59:28 -0400
Processing by PositionsController#new as HTML
Company Load (0.7ms) SELECT DISTINCT "companies".* FROM "companies"
LaborCategory Load (0.6ms) SELECT "labor_categories".* FROM "labor_categories" WHERE "labor_categories"."company_id" IN (4, 2, 6, 7, 3, 1, 5)
BrlFamily Load (0.8ms) SELECT "brl_families".* FROM "brl_families" WHERE "brl_families"."labor_category_id" IN (9, 10, 11, 5, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 14, 15, 16, 17, 6, 7, 8, 1, 2, 3, 4, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 12, 13)
FbrlCode Load (1.6ms) SELECT "fbrl_codes".* FROM "fbrl_codes" WHERE "fbrl_codes"."brl_family_id" IN (9, 10, 11, 1, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 14, 15, 16, 17, 6, 7, 8, 2, 3, 4, 5, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 12, 13)
Position Load (0.8ms) SELECT "positions".* FROM "positions" WHERE "positions"."fbrl_code_id" IN (22, 23, 24, 25, 26, 27, 28, 29, 13, 14, 15, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334, 335, 336, 337, 338, 339, 340, 341, 342, 343, 344, 345, 346, 347, 348, 349, 350, 351, 352, 353, 354, 355, 356, 357, 358, 359, 360, 361, 362, 363, 364, 365, 366, 367, 368, 369, 370, 371, 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384, 385, 386, 387, 388, 389, 390, 391, 392, 393, 34, 35, 36, 16, 17, 18, 19, 20, 21, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 30, 31, 32, 33)
LaborCategory Load (0.4ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 9]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 9]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 9]]
LaborCategory Load (0.4ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 10]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 10]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 10]]
LaborCategory Load (0.3ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 11]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 11]]
LaborCategory Load (0.3ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 1]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 1]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 1]]
LaborCategory Load (0.4ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 66]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 66]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 66]]
LaborCategory Load (0.4ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 67]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 67]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 67]]
LaborCategory Load (0.2ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 68]]
...
LaborCategory Load (0.2ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 12]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 12]]
LaborCategory Load (0.1ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 13]]
CACHE (0.0ms) SELECT "labor_categories".* FROM "labor_categories" INNER JOIN "brl_families" ON "labor_categories"."id" = "brl_families"."labor_category_id" WHERE "brl_families"."id" = $1 LIMIT 1 [["id", 13]]
HireType Load (0.2ms) SELECT "hire_types".* FROM "hire_types"
ExperienceCategory Load (0.5ms) SELECT "experience_categories".* FROM "experience_categories"
Experience Load (0.4ms) SELECT "experiences".* FROM "experiences" WHERE "experiences"."experience_category_id" IN (1, 2, 3)
Rendered positions/_positions_experience_fields.html.erb (20.9ms)
Rendered positions/new.html.erb within layouts/application (489.6ms)
Rendered layouts/_header.html.erb (62.4ms)
Rendered layouts/_sidenav.html.erb (0.4ms)
Rendered layouts/_footer.html.erb (0.0ms)
Completed 200 OK in 564ms (Views: 514.4ms | ActiveRecord: 40.9ms)
这是一组非常大的查询，因此我将其截断。