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!
Define the Query optimisation
The query parser commonly generates a standard initial tree to correspond to an SQL query, with no doing any optimization. Such type of a canonical query tree denotes a relational algebra expression that is extremely inefficient if executed directly. A query commonly has many possible execution strategies, and the process of choosing a appropriate one for processing a query is termed as query optimization. The major guidelines that are applied throughout query optimization are:
a. Combine a cascade of selections
b. Combine a cascade of projections
c. Commute selection and projection
d. Commuting selection with join / cartesian product Commuting projection with join or cartesian product
e. Commute projection with set operations
f. Commute selection with set operations
Express types of information available in MySQL? Information as regards the result of queries: This includes number of records affected by any SELECT or UPDATE or DELETE st
Describe the GRANT function and explain, how it associates to security. What kind of privileges may be granted? How are they revoked? Ans: Since more than one user can aacce
Data Manipulation Language Data manipulation language (DML) describes a set of commands that are used to query and change data within existing schema objects. In this case comm
I need help with some assignments
Outer Join: The use of Outer Join is that it still joins those tuples that do not have matching values in common columns are also contained in the result table. Outer join places
(1) Insert into PERSON Violated constraint: - Key constraint Reason: - Primary key 1 already exists in PERSON. Dealing: - DBMS could ask the user to provide valid PER
Define weak and strong entity sets? Weak entity set: entity set that do not have key attribute of their own are known as weak entity sets. Strong entity set
Explain the concept of a data model ? Data Model - Model is an abstraction procedure which hides irrelevant details although highlighting details relevant to the application
List any eight applications of DBMS. a) Universities b) Airlines c) Banking d) Credit card transactions e) Tele communication f) Sales g)Finance h) Manufac
what are the limitations of dbms?
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