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 ...
db.collection.aggregate([ { $group: { _id: { field1: "$field1", field2: "$field2" }, // 根据需要检查的字段进行分组 count: { $sum: 1 }, // 统计每个分组的文档数量 duplicates: { $addToSet: "$_id" } // 将重复的文档的_id添加到数组中 } }, { $match: { count: { $gt: 1...
db.mycoll.count() db.mycoll.copyTo(newColl) - duplicates collection by copying all documents to newColl; no indexes are copied. db.mycoll.convertToCapped(maxBytes) - calls {convertToCapped:'mycoll', size:maxBytes}} command db.mycoll.dataSize() db.mycoll.distinct( key ) - e.g. db....
db.mycoll.count() db.mycoll.copyTo(newColl) - duplicates collection by copying all documents to newColl; no indexes are copied. db.mycoll.convertToCapped(maxBytes) - calls {convertToCapped:'mycoll', size:maxBytes}}command db.mycoll.dataSize() db.mycoll.distinct( key ) - e.g. db.m...
To remove the duplicates, you can include a $group stage to group by the state field: db.suppliers.aggregate([ { $project: { state: 1, _id: 0 } }, { $unionWith: { coll: "warehouses", pipeline: [ { $project: { state: 1, _id: 0 } } ]} }, { $group: { _id: "$state...
* @param sortField 排序字段 * @return */ public FindIterablefindMongoDbDocByIdDescSort(String dataBaseName, String collectionName, String startId,String endId,String sortField){ return findMongoDbDocById(dataBaseName,collectionName,startId,endId).sort(new Document().append(sortField, -1)); ...
创建多列索引 语法:db.集合名.ensureIndex({field1:1/-1,field2:1/-1}) 对name 和age 建立一个复合索引,可以使用 db.集合名.getIndexes() 查看创建的索引情况3、子文档索引语法: db.集合名.ensureIndex({field.subfield:1/-1}) 如下文档可以建立子文档索引...
Enable data compliance and bolster security with powerful field-level data obfuscation. Choose from a variety of masking methods that let you anonymize each field and field type as needed. Learn more Reschema Move an existing collection to a new schema in a few clicks, or tune up your current...
创建多列索引 语法:db.集合名.ensureIndex({field1:1/-1,field2:1/-1}) 对name 和age 建立一个复合索引,可以使用 db.集合名.getIndexes() 查看创建的索引情况3、子文档索引 语法: db.集合名.ensureIndex({field.subfield:1/-1}) 如下文档可以建立子文档索引{...
Enable data compliance and bolster security with powerful field-level data obfuscation. Choose from a variety of masking methods that let you anonymize each field and field type as needed. Learn more Reschema Move an existing collection to a new schema in a few clicks, or tune up your current...