What is SQL ?

What is SQL ?

SQL stands for Structured Query Language. It’s the most standard language for accessing relational database management systems (RDMS). SQL is used to store data to and retrieve it from a database . It is used in database systems such as MySQL ,Oracle, PostgreSQL, Sybase,and Microsoft SQL Server, among others.

There’s an ANSI standard for SQL, and database system such as MySQL generally strive to implement this standard. There are Some subtle difference between standard SQL and MySQL’s SQL . Some of these difference are planned to become standard in future versions of MySQL and some are deliberate difference .

Published By Bhupendra Chahar

What is a Cookie ?

What is a Cookie ?

A Cookies is a small piece of information thar scripts can store on a client-side machine. You can set a Cookie on a user’s machine by sending as HTTP header containing data in the following format:-

Set-Cookie: NAME=VALUE; [expires=DATE;] [path=PATH;]

[domain=DOMAIN_NAME;] [secure]

This create a cookie called NAME with the value VALUE. The other parameters are all options. The expires field sets a date beyond which the cookie is no longer relavent (Note that if no expiry date is set , the cookie is effective permanent unless you or the user manually delete it ). Together, the path and domain can be used to specify the URL or URLs for which the cookie is relevant . The secure keyword means that the cookie will not be sent over a plain HTTP connection.

When a browser connects to an URL, it first searches the cookie stored locally . If any of them are relevant to the URL being connected to , they will be transmitted back to the server .

Published By Bhupendra Chahar