As we know that MySQL supports foreign key for referential integrity but it does not support CHECK constraint. But we can emulate them by using triggers. It can be illustrated with the help of an example given below −ExampleSuppose we have a table named ‘car1’ which can have the fix ... Read More

We can apply the PRIMARY KEY constraint to a column of an existing MySQL table with the help of ALTER TABLE statement. SyntaxALTER TABLE table_name MODIFY colum_name datatype PRIMARY KEY;                  OR ALTER TABLE table_name ADD PRIMARY KEY (colum_name); Suppose we have the following table ... Read More

To define a variable in  C++, you need to use the following syntax −Syntaxdatatype variable_name;You need to know what type of data is your variable is going to hold and what it will be called. The variable name has constraints on what you can name it. Following are the rules ... Read More

Following is the required program.ExampleLive Demopublic class Tester {    static int factorial(int n) {       if (n == 0)          return 1;       else          return (n * factorial(n - 1));    }    public static void main(String args[]) {       int i, fact = 1;       int number = 5;       fact = factorial(number);       System.out.println(number + "! = " + fact);    } }Output5! = 120

Similarities between OSI and TCP / IP Reference ModelsBoth the reference models are based upon layered architecture.The layers in the models are compared with each other. The physical layer and the data link layer of the OSI model correspond to the link layer of the TCP/IP model. The network layers ... Read More

The Internet layer is responsible for logical transmission of data packets over the internet. It can be compared to the network layer of the OSI model.The main functions of the internet layer are −It transmits data packets to the link layer.It routes each of the data packets independently from the ... Read More

The data link layer (Layer 2) converts the raw transmission facility provided by the physical layer to a reliable and error-free link.The main functions of the data link layer are as follows −It breaks up the stream of bits into data frames having sizes from a few hundred to a ... Read More

A metropolitan area network (MAN) is a network with a size greater than LAN but smaller than a WAN. It normally comprises networked interconnections within a city that also offers a connection to the Internet.The distinguishing features of MAN areNetwork size generally ranges from 5 to 50 km. It may ... Read More

decodeURIComponentTo decode a URL component in JavaScript, use the decodeURLComponent() method.ExampleYou can try to run the following code to decode a URL component −           Check                      function display() {         ... Read More

The autocomplete attribute is used with form element to set the autocomplete feature on or off. If the autocomplete feature is on, the browser will automatically show values, based on what users entered before in the field. If the autocomplete feature is off, the browser won’t automatically show values, based on what ... Read More