1
我试图用minute
大于12如何使用MongoDB中的聚合框架执行此查询?
我的数据结构返回visits
看起来是这样的:
{ "_id" : "20120723/foobar/song/custom-cred",
"live_daily_count" : 4,
"metacontent" : { "date" : "20120723",
"live_daily_statable_slug" : "custom-cred",
"live_daily_statable_title" : "custom cred",
"live_daily_statable_type" : "Song",
"url" : "foobar/songs/custom-cred",
"user_slug" : "foobar" },
"visits" : [
{ "country_name" : "UK",
"iso_two_letter_country_code" : "UK",
"referer" : "http://localhost:3000/foobar/songs/no-title-with-space",
"minute" : 12,
"token_id" : "134300236111rcbmbmvv" },
{ "country_name" : "UK",
"iso_two_letter_country_code" : "UK",
"referer" : "http://localhost:3000/foobar/songs/no-title-with-space",
"minute" : 13,
"token_id" : "134300242111pjvkjjkf" },
{ "country_name" : "UK",
"iso_two_letter_country_code" : "UK",
"referer" : "http://localhost:3000/foobar/songs/no-title-with-space",
"minute" : 13,
"token_id" : "134300243511udbnqldm" }
]
}
我使用MongoDB的Ruby驱动程序。我试着用以下:
conn = Mongo::Connection.new
db = conn['foobar_development']
cmd = {
aggregate: 'live_daily_stats',
pipeline: [
{ '$match' => { :_id => "20120723/foobar/song/custom-cred" } },
{ '$project' => {
:visits => 1,
} },
{ '$unwind' => '$visits' },
# { '$group' => {
# :_id => '$_id'
# } },
]
}
res = db.command(cmd)['result']
现在返回:
[
[0] {
"_id" => "20120723/foobar/song/custom-cred",
"visits" => {
"country_name" => "UK",
"iso_two_letter_country_code" => "UK",
"referer" => "http://localhost:3000/foobar/songs/custom-cred",
"minute" => 12,
"token_id" => "134300236111rcbmbmvv"
}
},
[1] {
"_id" => "20120723/foobar/song/custom-cred",
"visits" => {
"country_name" => "UK",
"iso_two_letter_country_code" => "UK",
"follower_class" => "non_follower",
"referer" => "http://localhost:3000/foobar/songs/custom-cred",
"minute" => 13,
"token_id" => "134300242111pjvkjjkf"
}
},
[2] {
"_id" => "20120723/foobar/song/custom-cred",
"visits" => {
"country_name" => "UK",
"iso_two_letter_country_code" => "UK",
"follower_class" => "non_follower",
"referer" => "http://localhost:3000/foobar/songs/custom-cred",
"minute" => 13,
"token_id" => "134300243511udbnqldm"
}
}
]
如何确保结果只有visits
比12 minute
更大的回报?任何帮助,将不胜感激。
难道你不想让$放开字段$访问(什么是$ data?)。我认为$ unwind只适用于数组(你的访问不是)。 – Thilo 2012-07-25 01:15:24
查看我的编辑,在'$ unwind'上。仍然是'[]'的结果。其次,我应该改变我的数据结构,以便它使用数组而不是散列?有什么办法可以使用哈希来代替数组?为什么我使用哈希值没有特别的理由。只是个人喜好 – 2012-07-25 01:25:39
你有没有考虑过使用单独的收集访问日志?这会使这个特定的查询变得微不足道(当然,我们不知道你的其他查询)。 – Thilo 2012-07-25 01:27:36