FT

View is a data object which does not contain any data. Contents of the view are the resultant of a base table. They are operated just like base table but they don’t contain any data of their own. The difference between a view and a table is that views are definitions built on top of other tables (or views). If data is changed in the underlying table, the same change is reflected in the view. A view can be built on top of a single or multiple tables. A database view is known as a “virtual table” that allows you to query the data in it. Understanding the database views and using them correctly are very important. we will discuss the database views, how they are implemented in MySQL,A view contains rows and columns, just like a real table. The fields in a view are fields from one or more real tables in the database. Introduction to Database View Why views ? 1-Views can be effective copies of base tables. 2-Views can be used in INSERT/UPDATE/DELETE. 3-Views can be views of vie...

PDO advantage : 1-Object Oriented 2-Bind parameters in statements (security) 3-Allows for prepared statements and rollback functionality (consistency) 4-Throws catcheable exceptions for better error handling (quality) 5-Exception mode; no need to check error state after each API call. It's best to tell PDO how you'd like the data to be fetched. You have the following options: 1-PDO::FETCH_ASSOC: returns an array indexed by column name. 2-PDO::FETCH_BOTH: (default):returns an array indexed by both column name and number. 3-PDO::FETCH_BOUND:Assigns the values of your columns to the variables set with the ->bindColumn() method. 4-PDO::FETCH_CLASS: Assigns the values of your columns to properties of the named class. It will create the properties if matching properties do not exist. 5-PDO::FETCH_INTO:Updates an existing instance of the named class. 6-PDO::FETCH_LAZY: Combines. 7-PDO::FETCH_BOTH/PDO:FETCH_OBJ, creating the object variable names as t...