MongoDB stores data in flexible, JSON-like documents, meaning fields can vary from document to document and data structure can be changed over time.

• MongoDB Manual;
• About mongodb @ stackoverflow;
• docs
  MongoDB Examples
• Structuring Document Data
• Stack Overflow;
• MongoDB Architecture Guide;

命令

• 在 linux 下將 /usr/local/mongodb/bin/ 加到 PATH段化。
• mongo 即可進入
• 示例如下嘁捷，詳解見后。

> help
> db.help()
> db.mycoll.help()
> db.d_321100.find( {"VALUE": new BinData(0,"MzIxMTkxMjEwMDAxNDk=") } ).sort({TM:-1}).limit(1)
> db.d_321100.find( {SN: { $regex: /-32119121000149-/ }, TYPE: 101 } ).sort({TM:-1}).limit(1).pretty()
> db.d_321100.find( {SN: { $regex: /-32119121000149-/ }, TYPE: {$in:[101,102]} } ).sort({TM:-1}).limit(1)
> db.d_321100.find( {SN: { $regex: /-32119121000149-/ }, TYPE: {$in:[101,102]} } ).count()

庫 libmongoc

• A Cross Platform MongoDB Client Library for C. 站內(nèi)搜索做的好显熏，可以很方便查看 數(shù)據(jù)結(jié)構(gòu)和函數(shù)說明雄嚣。

help

• > help
  
  MongoDB help
• > db.help()
• > db.mycoll.help() 指定的 mycoll 集合的方法
  
  help on collection methods
• db.d_320100.getIndexes 查當(dāng)前索引
  
  db.d_320100.getIndexes()

示例

• 以 PAIBO 標準為示例。
• 指定場所是否有場所心跳數(shù)據(jù)喘蟆？
  由于場所心跳UDP數(shù)據(jù)包的內(nèi)容就是場所編碼缓升，因此直接搜索所存儲的二進制數(shù)據(jù)即可：
• MongoDB Shell: find by BinData。
• 場所編碼 32119121000149（base64值：MzIxMTkxMjEwMDAxNDk=）最近一條場所心跳數(shù)據(jù)：

db.d_321100_XXXXXXXXX.find( {"VALUE": new BinData(0,"MzIxMTkxMjEwMDAxNDk=") } ).sort({TM:-1}).limit(1)
{ "_id" : ObjectId("5c46c6cda1b9402f388908ad"), 
"SN" : "321100---0-7621138-SITESTATUS-0", 
"TM" : NumberLong("1548142285103"), 
"UTM" : NumberLong("1548142285518"), 
"FLAG" : NumberLong(200),
"TYPE" : 105, 
"VALUE" : BinData(0,"MzIxMTkxMjEwMDAxNDk=")
}

pretty 格式示例

• 場所編碼 32119121000149（位于 SN 中）蕴轨，終端上下線（TYPE 101）的最近一條格式化數(shù)據(jù)

> db.d_321100_XXXXXXXXX.find( {SN: { $regex: /-32119121000149-/ }, TYPE: 101 } ).sort({TM:-1}).limit(1).pretty()
{
    "_id" : ObjectId("5c46f3eca1b9402f38b06e8f"),
    "SN" : "321100-32119121000149-XXXXXXXXX749D79E98850-1548152023-7876037-WA_SOURCE_FJ_0001",
    "TM" : NumberLong("1548153836614"),
    "UTM" : NumberLong("1548153836707"),
    "FLAG" : NumberLong(200),
    "TYPE" : 101,
    "VALUE" : BinData(0,"Vjk2dDVyd1VRdmp2V0VNcjVRPT0=")
}
注：示例中的 VALUE 字段值經(jīng)過裁剪港谊。即使未經(jīng)裁剪，也是加密過的數(shù)據(jù)橙弱。

• 場所編碼 32119121000149（位于 SN 中）歧寺，終端上下線（TYPE 101）或者虛擬身份（102）的最近一條數(shù)據(jù)：

> db.d_321100_XXXXXXXXX.find( {SN: { $regex: /-32119121000149-/ }, TYPE: {$in:[101,102]} } ).sort({TM:-1}).limit(1)

• 場所編碼 32119121000149（位于 SN 中），終端上下線（TYPE 101）或者虛擬身份（102）一共有多少條數(shù)據(jù)：

> db.d_321100_XXXXXXXXX.find( {SN: { $regex: /-32119121000149-/ }, TYPE: {$in:[101,102]} } ).count()
1580

正則搜索

• Selects documents where values match a specified regular expression.
• Provides regular expression capabilities for pattern matching strings in queries. MongoDB uses Perl compatible regular expressions (i.e. “PCRE” ) version 8.41 with UTF-8 support.

文本搜索

• Text Search
  Performs text search.
• MongoDB supports query operations that perform a text search of string content. To perform text search, MongoDB uses a text index and the $text operator.
• A collection can only have one text search index, but that index can cover multiple fields.

方法

• cursor.pretty()