99.99%availability for customers 9M+vehicles serviced AUTOMOTIVE “We use MongoDB as the core database for our services, so any new innovative idea or new service we build, we automatically say, ‘We’re going to use MongoDB as the core platform,’ knowing that it’s going to give us ...
g. -f name,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 ...
const size_t min = distribution.numberOfChunksInShardWithTag(to, tag); //如果分片的条目数已超过每个分片的最佳块数,则不要使用分片 if (min >= idealNumberOfChunksPerShardForTag) return false; const size_t imbalance = max - idealNumberOfChunksPerShardForTag; // 检查是否超过阈值,需要调整 if ...
优化器将仅考虑执行Index Filters指定的索引(When an index filter exists for the query shape, MongoDB ignores thehint(). To see whether MongoDB applied an index filter for a query shape, check theindexFilterSetfield of either thedb.collection.explain()or thecursor.explain()method.)...
# Check replica set status rs.status() arbiterOnly: true:作为仲裁者节点,它不参与数据的复制和写操作,仅用于投票以支持副本集的读写操作。 「Read Preferences」 Read Preferences是MongoDB官方提供集群操作偏好,这对于优化读取性能、确保数据一致性或跨多个服务器分配读取负载非常有用。
You can easily check if the field contains a string or not in MongoDB by using $regex and $text operators. MongoDB also offers more methods to find a
方法: MongoDB中的集合查询(获取一组文档中某个字段的不同值列表) 运用方法:DBCollection对象方法中的 distinct() 语句: 语句结构:distinct(key,[query]) key字符串,指定获取哪个字段的不同值;query:包含标准查询选项的对象,指定了要从哪个文档
Check out thesharding manualorsharding methodsin the MongoDB documentation. How does MongoDB sharding work? In MongoDB, asharded clusterconsists of shards, routers, and config servers. The data is distributed across the shards, the routers handle client requests, and the config servers maintain th...
"checkDigit" : "4" }, "lastName" : "zzz", "copiesSold" : 5 } 投影出新数组字段 示例数据: { "_id" : ObjectId("55ad167f320c6be244eb3b95"), "x" : 1, "y" : 1 } 下面的聚合操作将返回新的数组字段myArray: db.collection.aggregate( [ { $project: { myArray: [ "$x", "$...
test(NODE-6692): check that event emitters have error listeners (#4382) Feb 6, 2025 .gitignore fix(NODE-6845): ensure internal rejections are handled (#4448) Mar 14, 2025 .mocharc.js fix(NODE-6845): ensure internal rejections are handled (#4448) ...