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If on every legal database instant, the two expressions generate the same set of tuples, the expressions are called as

If on every legal database instant, the two expressions generate the same set of tuples, the expressions are called as Correct Answer Equivalent

If on every legal database instant, the two expressions generate the same set of tuples, the expressions are called as Equivalent relational algebra expressions. The order of the tuples is completely irrelevant for equivalency.

Related Questions

Which one of the following provides the ability to query information from the database and to insert tuples into, delete tuples from, and modify tuples in the database?
Consider two database relations R and S having 3 tuples in R and 2 tuples in S. what is the maximum number of tuples that could appear in the natural join of R and S?
You are the administrator of a SQL Server 2000 computer. The server contains a database named FinanceData that is used by a client/server application. Each employee has a SQL Server login that the application uses to access the server.Your company hires a new employee named Andrew. You create a SQL Server login named Andrew. You also create a database user named Andrew in the database and grant the database user full permissions in the database.Whenever Andrew runs the client/server application, he receives the following error message: "Invalid object name." Andrew also reports that he cannot access the database by using the application.You need to ensure that Andrew can use the application. Which Transact-SQL statement should you execute?
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In a _____________ operations do not wait for requests to produce tuples, but instead generate the tuples eagerly.
Below a set of instructions is given on preparation of instant coffee. Using the instructions, fill in the blank in the sentence given below.
(i) Boil water.
(ii) Take one teaspoon each of instant coffee and sugar.
(iii) Add boiling water and stir the mixture vigorously.
(iv) Warm milk separately.
(v) Add warm milk to the mixture and stir.
(iv) Hot instant-coffee is ready to drink.
A ________ on an attribute of a relation is a data structure that allows the database system to find those tuples in the relation that have a specified value for that attribute efficiently, without scanning through all the tuples of the relation.
In the following question, two statements are given each followed by two conclusions I and II. You have to consider the statements to be true even ifthey seem to be at variance from commonly known facts. You have to decide which of the given conclusions, if any, follows from the given statements. Statements:
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(II) A set is a subset of power set. Conclusion:
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(II) A set is a subset of power set.
Extortion is . . . . . . . . if the offender at the time of committing an extortion, is in the presence of the person put in fear, and commits the extortion by putting that person in fear of instant death, of instant hurt or of instant wrongful restraint to that person or to some other person, and, by so putting in fear, induces the person to put in fear then and there to deliver up the thing extorted.
With reference to the National Legal Services Authority, consider the following statements: 1. Its objective is to provide free and competent legal services to the weaker sections of society on the basis of equal opportunity. 2. It issues guidelines for the State Legal Services Authorities to implement the legal programmes and schemes throughout the country. Which of the statements given above is/are correct?