Explain the exists and unique functions of sql, Database Management System

Assignment Help:

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 match the criteria it returns true, or else it returns false. This provides you a clean, well-organized way to write a stored procedure in which does either an insert or update.

UNIQUE: If UNIQUE is particular then only unique values are used to compute the mean.

Related Discussions:- Explain the exists and unique functions of sql

Primary index, Primary index A primary index is a file that has a sorte...

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.

Normalize table 3nf , Normalize the following tables upto and including the...

Normalize the following tables upto and including the 3NF. Submit a 1 page printout of only the final set of normalized tables in Data Architect. Just use Data Architect to do the

Sql, example of embedded SQL query

example of embedded SQL query

What are the reasons of bucket overflow, What are the reasons of bucket ove...

What are the reasons of bucket overflow? Explain any two methods for solving this problem. Ans: It is general for file structures to be divided into equal-length partitions, k

Describe the relational model, a) Distinguish between ‘database' and ‘Data...

a) Distinguish between ‘database' and ‘Database Management Systems (DBMS)'. b) List and briefly describe five potential benefits of the database approach compared to conventio

The result of the union operation between r1 and r2, The result of the UNIO...

The result of the UNION operation between R1 and R2 is a relation that includes? The result of the operation between R1 and R2 includes all the tuples of R1 and R2 which have c

For known, What are the function of DBA?

What are the function of DBA?

What is the main advantage of the object model, What is the main advantage ...

What is the main advantage of the object model? What are its different components? The object model focuses on the logical data structures. Each object model comprises of many

Data models, what is stracture of dabms

what is stracture of dabms

What is a transaction? and how does it differs from update, wh

Write Your Message!

Name

Email id

Message

Verfication Code

Assured A++ Grade

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!

Submit Assignment

User Account

All Pages