当我在我的控制台中执行此操作时，它不会将值保存在我的记录中：
[87] pry(main)> Node.with_tagged_users.each do |node|
[87] pry(main)* tagged_users = node.tagged_users
[87] pry(main)* node.cached_tagged_user_names << tagged_users.map(&:name)
[87] pry(main)* node.save!
[87] pry(main)* end
Node Load (0.5ms) SELECT "nodes".* FROM "nodes" WHERE (cached_num_user_tags > 0)
User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."email" = 'gerry@test.com' LIMIT 1
User Load (0.3ms) SELECT "users".* FROM "users" WHERE "users"."email" = 'danny@test.com' LIMIT 1
(0.1ms) BEGIN
ActsAsTaggableOn::Tag Load (1.9ms) SELECT "tags".* FROM "tags" WHERE (LOWER(name) = LOWER('gerry@test.com') OR LOWER(name) = LOWER('danny@test.com'))
ActsAsTaggableOn::Tag Load (0.9ms) SELECT "tags".* FROM "tags" INNER JOIN "taggings" ON "tags"."id" = "taggings"."tag_id" WHERE "taggings"."taggable_id" = $1 AND "taggings"."taggable_type" = $2 AND (taggings.context = 'user_tags' AND taggings.tagger_id IS NULL) [["taggable_id", 85], ["taggable_type", "Node"]]
(0.1ms) COMMIT
User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."email" = 'gerry@test.com' LIMIT 1
User Load (0.3ms) SELECT "users".* FROM "users" WHERE "users"."email" = 'abc@test.com' LIMIT 1
(0.1ms) BEGIN
ActsAsTaggableOn::Tag Load (0.3ms) SELECT "tags".* FROM "tags" WHERE (LOWER(name) = LOWER('gerry@test.com') OR LOWER(name) = LOWER('abc@test.com'))
ActsAsTaggableOn::Tag Load (0.3ms) SELECT "tags".* FROM "tags" INNER JOIN "taggings" ON "tags"."id" = "taggings"."tag_id" WHERE "taggings"."taggable_id" = $1 AND "taggings"."taggable_type" = $2 AND (taggings.context = 'user_tags' AND taggings.tagger_id IS NULL) [["taggable_id", 86], ["taggable_type", "Node"]]
(0.1ms) COMMIT
=> [#<Node id: 85, name: "House Fire 2", family_tree_id: 57, user_id: 57, media_id: 228, media_type: "Video", created_at: "2015-05-15 00:20:26", updated_at: "2015-06-03 00:10:17", circa: nil, is_comment: nil, cached_votes_total: 0, cached_votes_score: 0, cached_votes_up: 0, cached_votes_down: 0, cached_weighted_score: 0, cached_weighted_total: 0, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, danny@test.com", cached_num_user_tags: 2, cached_tagged_user_names: [["Gerry Atrick", "Daniel Marty"]]>,
#<Node id: 86, name: "10PP Form Video", family_tree_id: 57, user_id: 57, media_id: 229, media_type: "Video", created_at: "2015-05-15 01:26:28", updated_at: "2015-06-03 00:37:56", circa: nil, is_comment: nil, cached_votes_total: 1, cached_votes_score: 1, cached_votes_up: 1, cached_votes_down: 0, cached_weighted_score: 1, cached_weighted_total: 1, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, abc@test.com", cached_num_user_tags: 2, cached_tagged_user_names: [["Gerry Atrick", "Marcamus Prime"]]>]
[88] pry(main)> Node.last
Node Load (0.5ms) SELECT "nodes".* FROM "nodes" ORDER BY "nodes"."id" DESC LIMIT 1
=> #<Node id: 86, name: "10PP Form Video", family_tree_id: 57, user_id: 57, media_id: 229, media_type: "Video", created_at: "2015-05-15 01:26:28", updated_at: "2015-06-03 00:37:56", circa: nil, is_comment: nil, cached_votes_total: 1, cached_votes_score: 1, cached_votes_up: 1, cached_votes_down: 0, cached_weighted_score: 1, cached_weighted_total: 1, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, abc@test.com", cached_num_user_tags: 2, cached_tagged_user_names: []>
请注意，在COMMIT之后，如果查看Node对象的最后一个属性/列，它就有一个如下数组的数组：cached_tagged_user_names: [["Gerry Atrick", "Marcamus Prime"]]>]这是正确的。
但是，一旦我通过Node.last在控制台中重新加载该对象，如果你查看最后一列，它就是空的。即使每个其他列都与看似成功的版本相同。
这对于所有nodes都是一致的，在这种情况下只是2。
可能导致此值无法正确保存的原因是什么？
这是我db/schema.rb中与该值对应的列：
t.string "cached_tagged_user_names", default: [], array: true
修改1
我也尝试过node.save而且也没有用。
修改2
如果我手动将元素一次添加到该属性的任何记录中，它会正确保存。 E.g：
[92] pry(main)> g
=> "gerry@test.com"
[93] pry(main)> m.cached_tagged_user_names << g
=> ["gerry@test.com"]
[94] pry(main)> m
=> #<Node id: 86, name: "10PP Form Video", family_tree_id: 57, user_id: 57, media_id: 229, media_type: "Video", created_at: "2015-05-15 01:26:28", updated_at: "2015-06-03 00:37:56", circa: nil, is_comment: nil, cached_votes_total: 1, cached_votes_score: 1, cached_votes_up: 1, cached_votes_down: 0, cached_weighted_score: 1, cached_weighted_total: 1, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, abc@test.com", cached_num_user_tags: 2, cached_tagged_user_names: ["gerry@test.com"]>
[95] pry(main)> m.save
(0.1ms) BEGIN
(0.1ms) COMMIT
=> true
[96] pry(main)> m
=> #<Node id: 86, name: "10PP Form Video", family_tree_id: 57, user_id: 57, media_id: 229, media_type: "Video", created_at: "2015-05-15 01:26:28", updated_at: "2015-06-03 00:37:56", circa: nil, is_comment: nil, cached_votes_total: 1, cached_votes_score: 1, cached_votes_up: 1, cached_votes_down: 0, cached_weighted_score: 1, cached_weighted_total: 1, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, abc@test.com", cached_num_user_tags: 2, cached_tagged_user_names: ["gerry@test.com"]>
[97] pry(main)> p = "Gerry Atrick"
=> "Gerry Atrick"
[98] pry(main)> m.cached_tagged_user_names << p
=> ["gerry@test.com", "Gerry Atrick"]
[99] pry(main)> m
=> #<Node id: 86, name: "10PP Form Video", family_tree_id: 57, user_id: 57, media_id: 229, media_type: "Video", created_at: "2015-05-15 01:26:28", updated_at: "2015-06-03 00:37:56", circa: nil, is_comment: nil, cached_votes_total: 1, cached_votes_score: 1, cached_votes_up: 1, cached_votes_down: 0, cached_weighted_score: 1, cached_weighted_total: 1, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, abc@test.com", cached_num_user_tags: 2, cached_tagged_user_names: ["gerry@test.com", "Gerry Atrick"]>
[100] pry(main)> m.save
(0.1ms) BEGIN
(0.1ms) COMMIT
=> true
[101] pry(main)> m
=> #<Node id: 86, name: "10PP Form Video", family_tree_id: 57, user_id: 57, media_id: 229, media_type: "Video", created_at: "2015-05-15 01:26:28", updated_at: "2015-06-03 00:37:56", circa: nil, is_comment: nil, cached_votes_total: 1, cached_votes_score: 1, cached_votes_up: 1, cached_votes_down: 0, cached_weighted_score: 1, cached_weighted_total: 1, cached_weighted_average: 0.0, cached_user_tag_list: "gerry@test.com, abc@test.com", cached_num_user_tags: 2, cached_tagged_user_names: ["gerry@test.com", "Gerry Atrick"]>
唯一突然出现的是，对于第二组值，它只是一个数组......而不是一个数组数组。但我认为Rails应该完美地处理这个问题，还是我错了？