Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Explain Record Based Logical Models?
Record-Based logical Models: Also define data at the conceptual and view levels. Unlike object-oriented models, are used to state overall logical structure of the database, and gives a higher-level description of the implementation. Named so since the database is structured in fixed-format records of various types. Each record type defines a fixed number of fields, or attributes. Each field is commonly of a fixed length (this simplifies the implementation). Record-based models do not involved a mechanism for direct representation of code in the database. Separate languages related along with the model are used to express database queries and updates. The three most widely-accepted models are the relational, network, and hierarchical.
Benefits of Hashed file Organisation 1. Insertion or search on hash-key is quick. 2. Best if equality search is required on hash-key. Drawbacks of Hashed file
Define entity integrity and referential integrity. How does SQL allow specification of these? Ans: Entity Integrity Rule- If the attribute A of relation R is a prime attribut
What is known as sequential file organization? In the sequential file organization, the records are kept in sequential order, according to the value of a "search key" of every
Describe entity referential integrity and integrity. Give an example of each. Entity Integrity Rule - If there is a attribute A of relation R is a prime attribute of R then A
Create a view emp_dep containing e_name and number of dependents from the tables employee and dependent of (i) CREATE VIEW emp_dept AS SELECT ename, COUNT(*) FROM employee, dep
how design database from begining
Give the two reasons for allowing concurrency
When is UPDATE_STATISTICS command used? - When processing of large data is done, this command is used. - Whenever large number of modification, deletions or copy takes place
In which format database schema is written ? Data base schema is written in the DDL format.
You group has been hired by TrainingrUs.com to keeps track of training revenues. TrainingrUS.com wants you to keep scheduling. COURSE table contains following information:
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd