by admin | Jun 16, 2015 | sem3
Codds Rules Dr Edgar F. Codd, once his intensive analysis on the relational Model of information systems, came up with twelve rules of his own, that consistent with him, a database should adjust so as to be considered a real relational database. These rules may be...
by admin | Jun 16, 2015 | sem3
ER Model to Relational Model In ER Model, when conceptualized into diagrams, gives a easy overview of entity-relationship, which is Simpler to understand. ER diagrams can be mapped to relational schema, that is, it is possible to create relational schema using ER...
by admin | Jun 16, 2015 | sem3
Heuristic cost estimation Using Heuristic cost estimation Process for heuristics optimization １．The parser of a high-level query generates an initial internal representation; ２．Apply heuristics rules to optimize the internal representation. ３．A query execution plan is...
by admin | Jun 16, 2015 | sem3
Query Processing and Optimization Query Processing and Optimization : Outline Operator Evaluation Strategies Query processing in general Selection Join Query Optimization Heuristic query optimization Cost-based query optimization Query Tuning Query Processing +...
by admin | Jun 16, 2015 | sem3
Embedded SQL Embedded SQL is a methodology of inserting inline SQL statements or queries into the source of a programming language, which is called as a host language. Because the host language can’t parse SQL, the inserted SQL is parsed by an embedded SQL...
by admin | Jun 16, 2015 | sem3
Database Objects A database objects in a relational database is a data structure used to either save or reference data. The most basic object that people interact with is the table. Other objects are indexes, stored procedures, sequences, views and many other. When a...
