Advanced MySQL: Stored Procedures,Subqueries,Views,Functions

Advanced queries are a part of every database administrator or developer job. Advanced queries must be handled delicately, because improperly coded SQL or poorly performing SQL can create bugs and application crashes. Advanced queries are typically used for reporting, joining multiple tables, nesting queries, and transaction locking.

The stored procedure is SQL statements wrapped within the CREATE PROCEDURE statement. The stored procedure may contain a conditional statement like IF or CASE or the Loops. The stored procedure can also execute another stored procedure or a function that modularizes the code.

A procedure (often called a stored procedure) is a subroutine like a subprogram in a regular computing language, stored in database. A procedure has a name, a parameter list, and SQL statement(s). All most all relational database system supports stored procedure, MySQL 5 introduce stored procedure.

A MySQL subquery is a query nested within another query such as SELECT, INSERT, UPDATE or DELETE. Also, a subquery can be nested within another subquery.

A MySQL subquery is called an inner query while the query that contains the subquery is called an outer query. A subquery can be used anywhere that expression is used and must be closed in parentheses.

A view is a database object that has no values. Its contents are based on the base table. It contains rows and columns similar to the real table. In MySQL, the View is a virtual table created by a query by joining one or more tables. It is operated similarly to the base table but does not contain any data of its own. The View and table have one main difference that the views are definitions built on top of other tables (or views). If any changes occur in the underlying table, the same changes reflected in the View also.

MySQL has a variety of functions you can use . examples includes aggregate functions , concat functions and character functions.