👉导读 MongoDB作为世界领先的文档型数据库广受开发者的喜爱,而 MongoDB 中的锁又为数据库高并发的读写提供了保障。本文从 MongoDB 的慢日志引入 MongoDB 中的锁,通过介绍 MongoDB 中的资源分类、锁分类、锁结构、锁实现以及锁的使用情况与查询方法,深入浅出地介绍 MongoDB 中锁的相关技术。长文干货,建议先...
age --fieldFile= file with field names - 1 per line --file= file to import from; if not specified, stdin is used --headerline use first line in input source as the field list (CSV and TSV only) --jsonArray treat input source as a JSON array --type= input format to import: ...
either json or csv (defaults to 'json') -o, --out= output file; if not specified, stdout is used --jsonArray output to a JSON array rather than one object per line --pretty output JSON formatted to be human-readable querying options: -q, --query= query filter, as a JSON...
{“hello":"world"} 这是一个Bson的例子,其中"hello"是key name,它一般是cstring类型,字节表示是cstring::= (byte*) "/x00" ,其中*表示零个或多个byte字节,/x00表示结束符;后面的"world"是value值,它的类型一般是string,double,array,binarydata等类型。 MongDB数据库本身支持多种开发语言的驱动,MongoDB有...
ArgumentValidation.CheckForNullReference(idList, "传入的对象idList为空"); MongoCollection<T> collection = GetCollection(); var query = Query.In("_id", new BsonArray(idList)); var result = collection.Remove(query); return result != null && result.DocumentsAffected > 0; ...
-o [ --out ] arg output file; if not specified, stdout is used --jsonArray output to a json array rather than one object per line 注意: 如果上面的选项-q指定一个查询条件,需要使用单引号括起来,如下所示: [plain]view plaincopy mongoexport -d page -c Article -q '{"spiderName": "mafen...
Because these values all come as strings and the movie release year is stored as an integer in MongoDB, the function must convert that value to an integer . We then build the query we will run against MongoDB: var castArray = [castMember]; var matchQuery = { Cast: { $in: cast...
The field name_idis reserved for use as a primary key; its value must be unique in the collection, is immutable, and may be of any type other than an array or regex. If the_idcontains subfields, the subfield names cannot begin with a ($) symbol. ...
The schema depth is defined as the maximum number of nested levels of keys in the schema. It does not matter if the subdocuments are nested directly or as elements of an array. An empty document has a depth of 0, whereas a document with some top-level keys but no nested subdocuments ...
NamePathTypeDescription documents documents array of object documents items documents object Update DocumentOperation ID: UpdateDocument You can use the updateOne endpoint to update a single record. Use the filter property in the request body to specify the search criteria. If more than one document...