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Pt1420 Unit 8

explanatory Essay
290 words
290 words
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1.8

Solution:1) List the names of all students majoring in computer science department(query)

2) change the major of smith to mechanical(update)

3) list the course names based on departments(query)

1.9

Solution: Controlled redundancy: Ensuring all the relavent data collected in one place and then collected into single database without any duplicates is called controlled redundancy.

For example take an organization which has two groups. The relavent data which is present in two groups must combined into a single database without any duplicates.

DBMS ensures the controlled redundancy over the data as the views of different users are combined during design phase.

Uncontrolled redundancy: If the data has redundancy

In this essay, the author

  • Explains that controlled redundancy entails ensuring all the data collected in one place and then collected into single database without any duplicates.
  • Explains that dbms ensures the controlled redundancy over the data as the views of different users are combined during design phase.
  • Explains that a section record to course record grade_report to student prerequisite record should be unique.
  • Explains the definition of data base management system, which is used to manage databases. entity is a thing or object or person about which the data can be collected.
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