我们希望查询年龄不等于null或空的记录。可以使用以下查询语句: db.collection.find({age:{ne:null,ne:""}}) SQL Copy 这将返回所有年龄不等于null或空的记录,即文档ID为1和4的记录: {"_id":1,"name":"Alice","age":25}{"_id":4,"name":"David"} SQL Copy 查询嵌套字段
//这里因为我们只设置了query,所以其它选项都是空的,.DBCollection.prototype.find = function(filter, projection, limit, skip, batchSize, options) { // Verify that API version parameters are not supplied via the shell helper. assert.noAPIParams(options); var cursor = newDBQuery(this._mongo, this...
mycoll.storageSize() - includes free space allocated to this collection db.mycoll.totalIndexSize() - size in bytes of all the indexes db.mycoll.totalSize() - storage allocated for all data and indexes db.mycoll.update(query, object[, upsert_bool, multi_bool]) - instead of two flags, ...
The query returns only the document where the item field has a value of null. Existence Check The following example queries for documents that do not contain a field. [1] The { item : { $exists: false } } query matches documents that do not contain the item field: db.inventory.find(...
demo.find([query],[fields]) - query is an optional query filter. fields is optional set of fields to return. e.g. db.demo.find( {x:77} , {name:1, x:1} ) db.demo.find(...).count() db.demo.find(...).limit(n) db.demo.find(...).skip(n) db.demo.find(...).sort(....
$match:匹配。$match: QUERY_DOC。QUERY_DOC见DBCollection.prototype.find,但不可以使用地理空间操作符。 $project:投射。$project: PROJECTION_DOC。PROJECTION_DOC见DBCollection.prototype.find。 $skip:跳过。$skip: N。跳过结果集的前N个文档。 $sort:排序。$sort: SORT_DOC。SORT_DOC见DBQuery.prototype.sort...
final TransactionStatus transaction = mongoTransactionManager.getTransaction(null); BasicDBObject query = new BasicDBObject(); query.put("appId", "1111"); try { final Integer newApplyTimeId = 12423423; Bson appIdBson = eq("appId", "1111"); Bson applyTimeIdBson = eq("applyTimeId", newAp...
Example 1: Query for Is Not Null Value on String Field Let’s use the find method to get all the documents that we will use for our example: > db.movies.find().pretty() { "_id" : ObjectId("60322d3501cd70079c48cb65"),
import static org.springframework.data.mongodb.core.query.Criteria.where; /** * @author xyding6 * @Classname MongoConfig * @Description TODO * @date 2023/2/21 */ @Configuration @Slf4j public class MongoConfig { @Value("${spring.data.mongodb.database}") ...
The query returns only the document where theitemfield has anullvalue: { "_id" : 900, "name" : null } Existence Check The{ name : { $exists: false } }query matches documents that do not contain theitemfield: db.users.find( { name : { $exists: false } } ) ...