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!
What is an Index?
An index is a small table having only two columns. The first column has a copy of the primary or candidate key of a table and the second column having a set of pointers holding the address of the disk block where that particular key value can be found.
The advantage of using index lies in the fact is that index makes search operation perform very fast. Suppose a table has a several rows of data, each row is 20 bytes wide. If you want to search for the record number 100, the management system must thoroughly read each and each row and after reading 99x20 = 1980 bytes it will search record number 100. If we have an index, the management system starts to search for record number 100 not from the table, but from the index. The index, having only two columns, might be just 4 bytes wide in each of its rows. After reading only 99x4 = 396 bytes of data from the index the management system search an entry for record number 100, reads the address of the disk block where record number 100 is stored and directly points at the record in the physical storage device. The result is a much faster access to the record (a speed benefit of 1980:396).
Explain the EXISTS and UNIQUE functions of SQL. Give an example for each? EXISTS: The EXISTS function takes one parameter that is a SQL statement. If any records exist which
find a name whose address is erode from student table
What is a foreign key, and what is it used for? A foreign key is used to establish relationships between relations in the relational model. Technically, a foreign key is a colu
Example -GRANT CREATE SESSION TO MCA12; (This command gives system level permission on creating a session - not portable) GRANT SELECT ON EMP TO MCA12; (Object level permi
The definition of the classes and operation can often be adjusted to increase the amount of inheritance". Justify the above statement. Adjustment of Inheritance The def
What is SQL Server Agent? SQL Server agent plays a significant role in the day-to-day tasks of a database administrator (DBA). It is often overlooked as one of the major tools
Explain the term- Query. Queries are used to repossess and show specific records in a table. They can also be used to show specific fields of specific records, which meet the co
why shadow copy technique is used?
as a customer service employee explain five measures you would recommend to make even a displeased students patronize the school canteen
Inheritance Adjustment As in object oriented analysis and design terms inheritance defines a relationship between classes, where as one class shares structure or behaviour def
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd