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!
The Structured Query Language
INTRODUCTION
Database is an organised set of information about an entity having controlled redundancy and serves numerous applications. DBMS (database management system) is application software that is developed to make and influence the data in database. A query language can simply access a data in a database. SQL (Structured Query Language) is language used by most relational database systems. IBM developed the SQL language in mid-1979. All communication with the RDBMS and the clients or among RDBMS is by SQL. Whether the client is a disguised engine or a basic SQL engine such as a GUI, one RDBMS talking to another or report writer, SQL statements pass from the client to the server. The server responds by processing the SQL and returning the results. The benefits of this approach are that the only network traffic is the first query and the resulting response. The processing power of the client is reserved for running the application.
SQL is a data sub-language having of three built-in languages: Data definition language (DDL), Data manipulation language (DML) and Data control language (DCL). It is a fourth generation language. SQL has many more benefits and features. It should be noted that a lot of commercial DBMS may or may not execute all the details given in this unit. For instance, MS-ACCESS does not support some of these features. Even some of the constructs may not be portable, please consult the DBMS Help for any such dissimilarity.
Saving Derived Attributes to Avoid Re-computation Data that is derived from other data should be stored in the computed form to avoid re-computation. For this, we could define
Describe association design of an object by giving one suitable example of it. The Design of Associations Associations are "glue" of advanced object oriented analysis and
Find out the names and company names of all employees sorted in ascending order of company name and descending order of employee names of by which company. SELECT EMPLOYEE_NAME,
Why, generally does an object-oriented system use the relational DBMS? The reasons for using relational DBMS for OO systems could be any combination of following: a. Many or
Consider a typical sales invoice that would include the following information. Design a single table to hold all of the information required to store an invoice including this info
Control as Concurrent Tasks The expression control as simultaneous task means applying control for those events of object which can happen simultaneously. An object can be imp
Give the general form of SQL query? Select A1, A2............., An From R1, R2..............., Rm Where P
An instance of relational schema R (A, B, C) has distinct values of A including NULL values. then A is a candidate key or not? If relational schema R (A, B, C) has distinct val
One-to-one relationship: For every 1:1 relationship type R in the ER diagram including two entities E1 and E2 we take one of entities (say E1) preferably with total participatio
let us consider a table having 2200 records and the fixed size of the table to be considered as 25.then how many numbers of table is requredto perform horizontal fragmentation
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