2. SQL Databases

2. SQL Databases
	Chapter 5. Distributed Applications

2. SQL Databases

2.1. SQL

2.1.1. Definition

Structured Query Language (SQL) is a standardized language for defining and manipulating data in a relational database.

2.1.2. The relational model of a database

Set of tables
Relationships are represented by values in tables.
Data is retrieved by specifying a result table that can be derived from one or more tables.

2.2. Stored Procedures

2.2.1. Definition

A stored procedure is a named collection of SQL statements and procedure logic that is compiled, verified, and stored in a server database.

2.2.2. Applications

Enforce data integrity
Perform system maintenance
Implement the server side of an application's logic.

2.3. Main points

2.3.1. Good points

SQL dominates the client/server market today.
It is easy to create applications in single-vendor/single-server environments.
There is a wealth GUI tools to create SQL applications.
SQL is familiar to millions of programmers and users.

2.3.2. Bad Points

SQL standards lag vendor implementations.
Incompatible vendors implementations.
Difficult in mount heterogeneous database environments.


1. Applications		3. TP Monitors