Technovation By SKS

1. Database concepts 1.1 Codd’s Rule for RDBMS – 12 Rule Rule 1: The Information Rule All data should be presented in a table form Rule 2: Guaranteed Access Rule All data should be accessible without ambiguity. Rule 3: Systematic Treatment of Null Values Support for Null values which is distinct from an empty string or a number with a value of zero. Rule 4: Dynamic Online Catalog based on the Relational model A relational database must provide access to its structure through the same tools that are used to access the data. Rule 5: Comprehensive Data Sublanguage Rule The DB must support at least one clearly defined language that includes functionality for Data Definition, Data Manipulation, Data Integrity, and Database Transaction Control. Rule 6: View Updating Rule Each view in the database should support the same full range of data manipulation that has direct access to a table available. In reality, providing update and delete access to logical views is difficult and is n...