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 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 attribute of R after that A cannot accept null values.
Referential Integrity Rule- In referential integrity, it is made sure that a value that appears in one relation for a given set of attributes as well appears for a particular set of attributes in another relation.
In SQL, referential integrity and entity integrity rules are implemented as constraints on the relation known as reference Key constraint and primary Key constraint correspondingly.
These constraints can be fixed with relation at the time of creation of the relations or after the creation of the relations by altering the definition of the relations. For instance:
compare the features of oracle RDBMS with MySQL and Microsoft SQL server
folding method and mid square method using visual basic
What are called journaling file systems? File systems that support log disks are known as journaling file systems.
What is the difference between a HAVING CLAUSE and a WHERE CLAUSE? HAVING CLAUSE - HAVING CLAUSE is used only with SELECT statement. - It is normally used in a GROUP BY
Primary index A primary index is a file that has a sorted series of records having two columns: a block address for that key field in the data file; and the ordering key field.
Entities Let us first be aware of the question: What are entities? An entity is an object of concern used to show the things in the actual world, e.g., table, car, bo
Give the Introduction of OBJECT DESIGN Strategies which are selected during system design are carried out in object-oriented design. In this procedure, objects which are identi
Difference between SQL and SQL*Plus SQL SQL*Plus SQL is a language SQL *Plus is an environment It is bas
Security: Data not needed by local applications is not stored at the site, therefore no unnecessary security violations may exist. But how can we carry out fragmentation? Fragm
In a job interview with a branch manager of a bank that operates in multiple Canadian provinces and the Yukon, you learn that all of the information is captured in real time in a s
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