You can create a table in a database using the CREATE TABLE query.SyntaxCREATE TABLE table_name( column1 datatype, column2 datatype, column3 datatype, ..... columnN datatype, PRIMARY KEY( one or more columns ) );To create a table in a database using JDBC API you need to −Register the Driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect ot the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password (String) as parameters to it.Create Statement: Create a Statement ... Read More
To get the size of all the documents in a query, you need to loop through documents. Let us first create a collection with documents −> db.sizeOfAllDocumentsDemo.insertOne({"StudentFirstName":"John", "StudentSubject":["MongoDB", "Java"]}); { "acknowledged" : true, "insertedId" : ObjectId("5cd3c0c1edc6604c74817cd7") } > db.sizeOfAllDocumentsDemo.insertOne({"StudentFirstName":"Larry", "StudentSubject":["MySQL", "PHP"], "StudentAge":21}); { "acknowledged" : true, "insertedId" : ObjectId("5cd3c0d9edc6604c74817cd8") } > db.sizeOfAllDocumentsDemo.insertOne({"StudentFirstName":"Chris", "StudentSubject":["SQL Server", "C#"], "StudentAge":23, "StudentCountryName":"US"}); { "acknowledged" : true, "insertedId" : ObjectId("5cd3c0fbedc6604c74817cd9") }Following is the query to display all documents from a collection with the help of find() method −> db.sizeOfAllDocumentsDemo.find().pretty();This will produce the following output −{ "_id" : ObjectId("5cd3c0c1edc6604c74817cd7"), ... Read More
To create two borders for a single component, use the createCompoundBorder() method in Java. Here, we have created LineBorder nd TitledBorder −LineBorder lineBorder = new LineBorder(Color.red); TitledBorder titleBorder = new TitledBorder("Demo Title"); Border border = BorderFactory.createCompoundBorder(lineBorder, titleBorder);Now, set both the borders for a single component −JButton button = new JButton("two borders"); button.setBorder(border);The following is an example to create two borders for a single component −Examplepackage my; import java.awt.BorderLayout; import java.awt.Color; import java.awt.Container; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.border.Border; import javax.swing.border.EtchedBorder; import javax.swing.border.LineBorder; import javax.swing.border.TitledBorder; public class SwingDemo { public static void main(String args[]) { ... Read More
To set the margins i.e. row and columns margins between cells of a table, use the setIntercellSpacing() method −Dimension dim = new Dimension(50, 2); table.setIntercellSpacing(new Dimension(dim));Above, we have used the Dimension class −The following is an example to set margins between cells of a JTable cell −Examplepackage my; import java.awt.Dimension; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JRootPane; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.DefaultTableModel; public class SwingDemo { public static void main(String[] argv) throws Exception { JFrame frame = new JFrame("Demo"); JPanel panel = new JPanel(); String data[][] = { ... Read More
While creating a table, in certain scenarios, we need values to column such as ID, to be generated/incremented automatically. Various databases support this feature in different ways.In MySQL database you can declare a column auto increment using the following syntax.CREATE TABLE table_name( ID INT PRIMARY KEY AUTO_INCREMENT, column_name1 data_type1, column_name2 data_type2, column_name3 data_type3, column_name4 data_type4, ............ ........... );While inserting records in a table there is no need to insert value under the auto-incremented column. These will be generated automatically.Setting the initial valueBy default, the initial value of the auto-incremented column will be 1. You ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Name varchar(100) -> ); Query OK, 0 rows affected (1.32 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('JOhn'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('CHRIS'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('DAVID'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('RObert'); Query OK, 1 row affected (0.21 sec)Display all records from the table using select statement −mysql> select *from DemoTable;Output+--------+ | Name ... Read More
Here we will see some improvements on selection sort. As we know that the selection sort works by taking either the minimum or maximum element from the array and place that element at correct position. In this approach, we want to sort the array in both ways. Here we will take the max and min simultaneously, then sort the array from two end. Let us see the algorithm to get better idea.AlgorithmtwoWaySelectionSort(arr, n)begin for i := 0, and j := n-1, increase i by 1, and decrease j by 1, until i>=j, do min := minimum ... Read More
The sizeof function (Sometimes called operator) is used to calculate the size of the given argument. If some other functions are given as argument, then that will not be executed in the sizeof.In the following example we will put one printf() statement inside the loop. Then we will see the output.Example#include double my_function() { printf("This is a test function"); return 123456789; } main() { int x; x = sizeof(printf("Hello World")); printf("The size: %d", x); x = sizeof(my_function()); printf("The size: %d", x); }OutputThe size: 4 The size: 8The printf() is not executed which is ... Read More
In C or C++, we cannot return more than one value from a function. To return multiple values, we have to provide output parameter with the function. Here we will see another approach to return multiple value from a function using tuple and pair STL in C++.The Tuple is an object capable to hold a collection of elements, where each element can be of different types.The pair can make a set of two values, which may be of different types. The pair is basically a special type of tuple, where only two values are allowed.Let us see one example, where ... Read More
You can insert records into a table using the INSERT query.SyntaxINSERT INTO TABLE_NAME (column1, column2, column3, ...columnN) VALUES (value1, value2, value3, ...valueN); Or, INSERT INTO TABLE_NAME VALUES (value1, value2, value3, ...valueN);To insert a record into a table in a database using JDBC API you need to −Register the Driver: Register the driver class using the registerDriver() method of the DriverManager class. Pass the driver class name to it, as parameter.Establish a connection: Connect to the database using the getConnection() method of the DriverManager class. Passing URL (String), username (String), password (String) as parameters to it.Create Statement: Create a Statement object using the createStatement() ... Read More