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510 questions and answers

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Describe various actions of a shift reduce parsers.

Actions of shift-reduce parsers: A shift-reduce parser works by doing some combination of Shift steps and Reduce steps, hence the name.

Demo Teacher
added 2 years ago
1051 views

What is the difference between a database and a table? Why are entity integrity and referential integrity important in a database?

Difference between database and a table: A table is an object inside a database. A database has tables of data, views, indexes and programs. A database can have 10 or thousands of tables.

Demo Teacher
added 2 years ago
1023 views

Explain two-phase locking protocol.

In a multiprogramming environment where multiple transactions can be executed simultaneously,

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added 2 years ago
991 views

Write short notes on the following:

  • Armstrong’s Axioms
  • Outer join

Armstrong’s Axioms: An inference axiom is a rule that states if a relation satisfies certain Functional Dependencies (FDs) then it must satisfy certain other FDs.

Demo Teacher
added 2 years ago
955 views

Write short notes on the following:

  • View Serializability
  • Codd’s Rules

View Serializability Let S and S0 be two schedules with the same set of transactions. S and S0 are view equivalent if the following three conditions are met:

Demo Teacher
added 2 years ago
1533 views

Describe the wait-die and wound-wait protocols for deadlock prevention. Define three concurrency problems: dirty read, non-repeatable read, phantoms.

We can prevent deadlocks by giving each transaction a priority and ensuring that lower priority transactions are not allowed to wait for higher priority transactions (or vice versa).

Demo Teacher
added 2 years ago
1005 views

Write short notes on:

  • Database Language
  • Metadata
  • B+ tree

A DBMS is a software package that carries out many different tasks including the provision of facilities to enable the user to access and modify information in the database.

Demo Teacher
added 2 years ago