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If you want the database location i.e. where it is created in MySQL, you can use system variable @@datadir.The syntax is as followsSELECT @@datadir;The following is the querymysql> select @@datadir;Here is the output. The above query returns the location+---------------------------------------------+ | @@datadir | +---------------------------------------------+ | C:\ProgramData\MySQL\MySQL Server 8.0\Data\ | +---------------------------------------------+ 1 row in set (0.00 sec)Now reach the above directory in your system. The screenshot of the ... Read More
A JSP can be used with an HTML form tag to allow users to upload files to the server. An uploaded file can be a text file or a binary or an image file or just any document.Creating a File Upload FormLet us now understand how to create a file upload form. The following HTML code creates an uploader form. Following are the important points to be noted down −The form method attribute should be set to the POST method and the GET method cannot be used.The form enctype attribute should be set to multipart/form-data.The form action attribute should be ... Read More
This example demonstrate about How to use trim () in Android textview.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 code to res/layout/activity_main.xml. In the above code, we have taken name as Edit text, when user click on button it will take data and trim the data without spaces.Step 3 − Add the following code to src/MainActivity.javapackage com.example.myapplication; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; import ... Read More
The lastIndexOf() method of the AbstractList return the index of the last occurrence of an element in the list. If the element does not exist in the list, then -1 is returned.The syntax is as followspublic int lastIndexOf(Object ob)Here, the parameter ob is the element to be searched. To work with the AbstractList class, import the following packageimport java.util.AbstractList;The following is an example to implement lastIndexOf() method of the AbstractlList class in JavaExample Live Demoimport java.util.ArrayList; import java.util.AbstractList; public class Demo { public static void main(String[] args) { AbstractList myList = new ArrayList(); myList.add(75); ... Read More
You can use $ne(Not Equal) operator for this. To understand the concept, let us create a collection with document. The query to create a collection with document is as follows −> db.arrayFieldIsNotEmptyDemo.insertOne({"StudentName":"Larry", "StudentTechnicalSubject":["Java", "C"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c76fe2f1e9c5dd6f1f78291") } > db.arrayFieldIsNotEmptyDemo.insertOne({"StudentName":"Mike", "StudentTechnicalSubject":[]}); { "acknowledged" : true, "insertedId" : ObjectId("5c76fe3b1e9c5dd6f1f78292") } > db.arrayFieldIsNotEmptyDemo.insertOne({"StudentName":"Sam", "StudentTechnicalSubject":["MongoDB"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c76fe491e9c5dd6f1f78293") } > db.arrayFieldIsNotEmptyDemo.insertOne({"StudentName":"Carol", "StudentTechnicalSubject":[]}); { "acknowledged" : true, "insertedId" : ObjectId("5c76fe521e9c5dd6f1f78294") } > db.arrayFieldIsNotEmptyDemo.insertOne({"StudentName":"David", "StudentTechnicalSubject":["MySQL", "SQL Server"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c76fe661e9c5dd6f1f78295") }Display all documents ... Read More
To delete all records of a collection in MongoDB shell, use the remove() method. The syntax is as follows −db.yourCollectionName.remove({});To understand the syntax, let us create a collection with document. The query to create a collection with document is as follows −> db.deleteAllRecordsDemo.insertOne({"StudentName":"John"}); { "acknowledged" : true, "insertedId" : ObjectId("5c8f6ca32f684a30fbdfd596") } > db.deleteAllRecordsDemo.insertOne({"StudentName":"Carol", "StudentAge":21}); { "acknowledged" : true, "insertedId" : ObjectId("5c8f6cb22f684a30fbdfd597") } > db.deleteAllRecordsDemo.insertOne({"StudentName":"Mike", "StudentAge":23, "Hobby":["Learning", "Photography"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c8f6cde2f684a30fbdfd598") }Display all documents from a collection with the help of find() method. The query is as follows −> db.deleteAllRecordsDemo.find().pretty();The following ... Read More
You can add a new column to a table using the ALTER TABLE command.SyntaxALTER TABLE table_name ADD column_name datatype;Assume we have a table named Sales in the database with 5 columns namely ProductName, CustomerName, DispatchDate, DeliveryTime, Price and, Location as shown below:+-------------+--------------+--------------+--------------+-------+----------------+ | ProductName | CustomerName | DispatchDate | DeliveryTime | Price | Location | +-------------+--------------+--------------+--------------+-------+----------------+ | Key-Board | Raja | 2019-09-01 | 08:51:36 | 7000 | Hyderabad | | Earphones | Roja | 2019-05-01 | 05:54:28 | 2000 ... Read More
A RowSet object is similar to ResultSet, it also stores tabular data, in addition to the features of a ResultSet a RowSet follows JavaBeans component model. This can be used as a JavaBeans component in a visual Bean development environment, i.e. in environments like IDE’s you can visually manipulate these properties.Connecting RowSet with databaseThe RowSet interface provides methods to set Java bean properties to connect it to the required database −void setURL(String url):void setUserName(String user_name):void setPassword(String password):PropertiesA RowSet object contains properties and each property have Setter and getter methods. Using these you can set and get values from a command ... Read More
To get a distinct aggregation of an array field across indexes, let us take an example and create a collection with some documents.Following is the query to create a collection with documents> db.distinctAggregation.insertOne({"UserName":"Larry", "UserPost":["Hi", "Hello"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c98aefb330fd0aa0d2fe4c6") } > db.distinctAggregation.insertOne({"UserName":"Chris", "UserPost":["Hi", "Good Morning"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c98af0a330fd0aa0d2fe4c7") } > db.distinctAggregation.insertOne({"UserName":"Robert", "UserPost":["Awesome"]}); { "acknowledged" : true, "insertedId" : ObjectId("5c98af1e330fd0aa0d2fe4c8") }Following is the query to display all documents from a collection with the help of find() method> db.distinctAggregation.find().pretty();This will produce the following output{ "_id" : ObjectId("5c98aefb330fd0aa0d2fe4c6"), ... Read More
To change the height of tableView cell in ios dynamically, i.e resizing the cell according to the content available, we’ll need to make use of automatic dimension property. We’ll see this with the help of an sample project.Create an empty project and go to it’s viewController class, conform it to UITableViewDataSource and UITableViewDelegate.Now, In the below code, we will first create a table, then register a cell for that table, and add some table properties.We’ll set the table view delegate and table view datasource.Finally we’ll add the table view to view. Then we’ll call this function inside the viewDidLoad method ... Read More