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You can achieve this with the help of an aggregate framework. To understand the concept, let us create a collection with the document. The query to create a collection with a document is as follows −> db.countGroupByDemo.insertOne({"StudentId":10, "StudentName":"John"}); { "acknowledged" : true, "insertedId" : ObjectId("5c7700871e9c5dd6f1f78296") } > db.countGroupByDemo.insertOne({"StudentId":10, "StudentName":"Carol"}); { "acknowledged" : true, "insertedId" : ObjectId("5c77008f1e9c5dd6f1f78297") } > db.countGroupByDemo.insertOne({"StudentId":20, "StudentName":"Sam"}); { "acknowledged" : true, "insertedId" : ObjectId("5c7700971e9c5dd6f1f78298") } > db.countGroupByDemo.insertOne({"StudentId":30, "StudentName":"Mike"}); { "acknowledged" : true, "insertedId" : ObjectId("5c7700a21e9c5dd6f1f78299") } > db.countGroupByDemo.insertOne({"StudentId":30, "StudentName":"David"}); { "acknowledged" : true, "insertedId" : ObjectId("5c7700aa1e9c5dd6f1f7829a") } ... Read More
In order to display the indexes of a collection, you can use getIndexes(). The syntax is as follows −db.yourCollectionName.getIndexes();To understand the concept, let us create a collection with the document. The query to create a collection with a document is as follows −> db.indexDemo.insertOne({"StudentName":"Larry", "StudentAge":21}); { "acknowledged" : true, "insertedId" : ObjectId("5c8f7c4f2f684a30fbdfd599") } > db.indexDemo.insertOne({"StudentName":"Mike", "StudentAge":24}); { "acknowledged" : true, "insertedId" : ObjectId("5c8f7c552f684a30fbdfd59a") }Display all documents from a collection with the help of find() method. The query is as follows −> db.indexDemo.insertOne({"StudentName":"Carol", "StudentAge":20});The following is the output −{ "acknowledged" : true, "insertedId" : ObjectId("5c8f7c5e2f684a30fbdfd59b") ... Read More
The CachedRowSet is the base implementation of disconnected row sets. It connects to the data source, reads data from it, disconnects with the data source and the processes the retrieved data, reconnects to the data source and writes the modifications.Creating a CachedRowSetYou can create a Cached RowSet object using the createCachedRowSet() method of the RowSetFactory.You can create a RowSetFactory object using the newfactory() method of the RowSetProvider method.Create a CachedRowSet object using the above-mentioned methods as shown below −//Creating the RowSet object RowSetFactory factory = RowSetProvider.newFactory(); CachedRowSet rowSet = factory.createCachedRowSet();Connecting to the data sourceAfter creating a RowSet object you need ... Read More
Search for a text in MongoDBs Double Nested Array with the help of dot(.) notation. Let us first create a collection. Following is the query to create a collection with documents> db.doubleNestedArrayDemo.insertOne( ... { ... "StudentId" : "1000", ... "StudentName" : "Larry", ... "StudentDetails" : [ ... { ... "ProjectName" : "Online Banking", ... "ProjectDetails" : [ ... { ... ... Read More
To create custom DateTime formatter, use DateTimeFormatter. Let us first see for Time −DateTimeFormatter dtFormat = new DateTimeFormatterBuilder() .appendValue(ChronoField.HOUR_OF_DAY) .appendLiteral(":") .appendValue(ChronoField.MINUTE_OF_HOUR) .appendLiteral(":") .appendValue(ChronoField.SECOND_OF_MINUTE) .toFormatter();For Date −dtFormat = new DateTimeFormatterBuilder() .appendValue(ChronoField.YEAR) .appendLiteral("/") .appendValue(ChronoField.MONTH_OF_YEAR) .appendLiteral("/") .appendValue(ChronoField.DAY_OF_MONTH) .toFormatter();Exampleimport java.time.LocalDateTime; import java.time.format.DateTimeFormatter; import java.time.format.DateTimeFormatterBuilder; import java.time.temporal.ChronoField; public class Demo { public static void main(String[] args) { DateTimeFormatter dtFormat = new DateTimeFormatterBuilder() .appendValue(ChronoField.HOUR_OF_DAY) .appendLiteral(":") .appendValue(ChronoField.MINUTE_OF_HOUR) .appendLiteral(":") .appendValue(ChronoField.SECOND_OF_MINUTE) .toFormatter(); System.out.println("Time = "+dtFormat.format(LocalDateTime.now())); dtFormat = new DateTimeFormatterBuilder() ... Read More
Let us first create a collection with documents −> db.likeDemo.insertOne({"Name":"John", Age:32}); { "acknowledged" : true, "insertedId" : ObjectId("5cb84984623186894665ae41") } > db.likeDemo.insertOne({"Name":"Chris", Age:25}); { "acknowledged" : true, "insertedId" : ObjectId("5cb84991623186894665ae42") } > db.likeDemo.insertOne({"Name":"Carol", Age:22}); { "acknowledged" : true, "insertedId" : ObjectId("5cb849a1623186894665ae43") } > db.likeDemo.insertOne({"Name":"Johnny", Age:22}); { "acknowledged" : true, "insertedId" : ObjectId("5cb849b2623186894665ae44") } > db.likeDemo.insertOne({"Name":"James", Age:27}); { "acknowledged" : true, "insertedId" : ObjectId("5cb849bb623186894665ae45") }Following is the query to display all documents from the collection with the help of find() method −> db.likeDemo.find().pretty();This will produce the following output −{ "_id" : ... Read More
You can use ORDER BY ASC to order timestamp values in ascending order with TIMESTAMP() method.The following is the syntax using TIMESTAMP() −SELECT timestamp( yourTimestampColumnName ) as anyAliasName From yourTableName order by 1 ASCTo understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table Timestamp_TableDemo -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> yourTimestamp timestamp -> ); Query OK, 0 rows affected (0.83 sec)Now you can insert some records in the table using insert ... Read More
Before getting into example, we should know what Intent service is in android. Intent Service is going to do back ground operation asynchronously. When user call startService() from activity , it doesn't create instance for each request. It going to stop service after done some action in service class or else we need to stop service using stopSelf().This example demonstrate about How to start intent service for every 10 sec’s.Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.Step 2 − Add the following ... Read More
To create a tuple from another collection, you need to use fromCollection() method.Let us first see what we need to work with JavaTuples. To work with Quintet class in JavaTuples, you need to import the following package −import org.javatuples.Quintet;Note − Steps to download and run JavaTuples program If you are using Eclipse IDE to run Quintet Class in JavaTuples, then Right Click Project → Properties → Java Build Path → Add External Jars and upload the downloaded JavaTuples jar file.The following is an example −Exampleimport org.javatuples.Quintet; import java.util.*; public class Demo { public static void main(String[] args) { ... Read More
For this, let us first create a new table in MySQLmysql> create table useProcedure - > ( - > Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, - > FirstName varchar(20), - > LastName varchar(20) - > ); Query OK, 0 rows affected (0.65 sec)Insert some records in the table using insert command.The query is as followsmysql> insert into useProcedure(FirstName, LastName) values('Adam', 'Smith'); Query OK, 1 row affected (0.27 sec)The following is your stored procedure to set two variables in a stored procedure with single select ... Read More