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To find the greatest value among four tables, you can use the method GREATEST(). Following is the query to create first table −mysql> create table DemoTable1 -> ( -> Value int -> ); Query OK, 0 rows affected (0.70 sec)Insert some records in the first table using insert command −mysql> insert into DemoTable1 values(10); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable1 values(60); Query OK, 1 row affected (0.14 sec)Display all records from the first table using select statement −mysql> select *from DemoTable1;Output+-------+ | Value | +-------+ | 10 | ... Read More
Here we will see the kbhit functionality in C. The kbhit is basically the Keyboard Hit. This function is present at conio.h header file. So for using this, we have to include this header file into our code.The functionality of kbhit() is that, when a key is pressed it returns nonzero value, otherwise returns zero.Example#include #include main() { char ch; printf("Enter keys (ESC to exit)"); while (1) { //define infinite loop for taking keys if (kbhit) { ch = getch(); // Get typed character into ch ... Read More
In C++ we can use the function overloading feature. Using this feature, we can create functions with same name. The only difference is the type of the arguments, and the number of arguments. The return type is not considered here. Now the question comes how the C++ distinguishes overloaded functions in object code?In the object code, it changes the name by adding information about the arguments. The technique which is applied here is called the Name Mangling. C++ has no standardized technique for name mangling. So different compiler uses different techniques.Here is an example of Name Mangling. The overloaded functions ... Read More
Whenever we execute SQL statements using the executeQuery() method, it returns a ResultSet object which holds the tabular data returned by the SELECT queries(in general). The ResultSet object contains a cursor/pointer which points to the current row. Initially this cursor is positioned before first row (default position).The ResultSet interface provides various methods to find, the no.of columns, name of the column, type of the column etc.. but, it does not provides any method to find the number of rows in a table directly.Using count(*) function in the SELECT query you can get the number of rows in a table as −select ... Read More
You can use $pull operator. Let us first create a collection with documents −> db.pullAnArrayElementDemo.insertOne( { "StudentDetails": [ { "StudentFirstName":"Chris", "StudentScore":56 }, {"StudentFirstName":"Robert", "StudentScore":59 } ] } ); { "acknowledged" : true, "insertedId" : ObjectId("5cd3b55bedc6604c74817cd5") }Following is the query to display all documents from a collection with the help of find() method −> db.pullAnArrayElementDemo.find().pretty();This will produce the following output −{ "_id" : ObjectId("5cd3b55bedc6604c74817cd5"), "StudentDetails" : [ { "StudentFirstName" : "Chris", "StudentScore" : 56 }, { ... Read More
To apply adjustments to the last column only, use the setAutoResizeMode and set the mode. The mode here would be AUTO_RESIZE_LAST_COLUMN. This will allow you to adjust only the last columns even if any of the column header is dragged to resize.Let us first see an example to create a table in Java −Examplepackage my; import java.awt.Color; import java.awt.Font; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.DefaultTableModel; public class SwingDemo { public static void main(String[] argv) throws Exception { DefaultTableModel tableModel = new DefaultTableModel(); JTable table = new JTable(tableModel); tableModel.addColumn("Technology"); ... Read More
At first, set the setShowGrid() to FALSE to disable all the grid lines. To display only vertical grid lines in a table, set the method setShowVerticalLines() to TRUE. Let us first create a table with rows and columns −String[][] rec = { { "1", "Steve", "AUS" }, { "2", "Virat", "IND" }, { "3", "Kane", "NZ" }, { "4", "David", "AUS" }, { "5", "Ben", "ENG" }, { "6", "Eion", "ENG" }, }; String[] header = { "Rank", "Player", "Country" }; JTable table = new JTable(rec, header);Now, display only vertical grid lines −table.setShowGrid(false); table.setShowVerticalLines(true);The ... Read More
Non-enumerable propertyObjects can have properties that don't show up when iterated through the particular object using Object.keys() or for...in loop.Those type of properties are called as non-enumerable properties.Creating a non-enumerable propertyTo create a non-enumerable property we have to use Object.defineProperty() method. This a special method to create non-enumerable properties in an object. In the following example, three properties such as name, age and country were created normally and a property named "salary" was created using Object.defineProperty() method and key named enumerable was assigned with false. When the object "person" got iterated using Object.keys() the properties such as name, age and country ... 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.For example, in a table if we have a column with name ID and data type ... Read More
In this section we will see how we can generate the gray codes of n bits using backtracking approach? The n bit gray code is basically bit patterns from 0 to 2^n – 1 such that successive patterns differ by one bit. So for n = 2, the gray codes are (00, 01, 11, 10) and decimal equivalent is (0, 1, 3, 2). The program will generate the decimal equivalent of the gray code values.AlgorithmgenerateGray(arr, n, num)begin if n = 0, then insert num into arr return end if generateGray(arr, n-1, ... Read More