Tag: databases

Questions Related to databases

Intermediate results of the user query is materialized at
technology databases

  1. Temporary Space

  2. Spool Space

  3. Permanent Space

  4. Any of the above

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Correct Option: B

An USER cannot have these if Permanent space is not allocated to it
technology databases

  1. Permanent Table and Stored Procedure

  2. Permanent View and Stored Procedure

  3. Macros and Stored Procedure

  4. None of the above

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Correct Option: A

When Database A has 5GB of spool space, Database B is created as child of Database A with 3GB of spool space, then Database A will have
technology databases

  1. 2GB of spool space

  2. 5GB of spool space

  3. 2GB of permanent space

  4. 3GB of spool space

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Correct Option: B

When the 'SELECT' clause of the SQL has the aggregate function, it is must to have this clause to prevent error
technology databases

  1. WHERE

  2. ORDER BY

  3. GROUP BY

  4. Aggregate Function

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Correct Option: C

Identify the OLAP function from the given options
technology databases

  1. MSUM

  2. SUM

  3. AVG

  4. All of the above

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Correct Option: A

Statistics cannot be collected on this table
technology databases

  1. Permanent Table

  2. Set Table

  3. Multiset Table

  4. Volatile Table

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Correct Option: D

What best describes the relationship between indexes and SQL performance?
technology databases

  1. Indexes are only used in special cases

  2. Indexes are used to make table storage more efficient

  3. Indexes rarely make a difference in SQL performance

  4. Indexes exist solely to improve query speed

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Correct Option: D

Which of the following is an important consideration when tuning an SQL statement?
technology databases

  1. The number of CPUs on the server

  2. The degree of parallelism on the tables

  3. The quality of the SQL optimization

  4. The use of bitmap indexes

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Correct Option: C

We refer to a join as a self-join when…
technology databases

  1. We are joining two tables only

  2. we are using left and right join together

  3. we are joining table to itself

  4. we are joining more than 2 tables

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Correct Option: C

Which SQL statement selects all rows from table called Contest, with column ContestDate having values greater or equal to May 25, 2006?
technology databases

  1. SELECT * FROM Contest WHERE ContestDate >= '05/25/2006'

  2. SELECT * FROM Contest GROUPBY ContestDate >= '05/25/2006'

  3. SELECT * FROM Contest WHERE ContestDate < '05/25/2006'

  4. SELECT * FROM Contest HAVING ContestDate >= '05/25/2006'

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Correct Option: A
Explanation:

To solve this question, the user needs to know the syntax of SQL SELECT statements, how to select all rows from a table, how to specify column names, and how to use the WHERE clause to filter rows based on a certain condition.

Now, let's go through each option and explain why it is right or wrong:

A. SELECT * FROM Contest WHERE ContestDate >= '05/25/2006': This option is correct. This statement selects all columns and rows from the Contest table where the ContestDate column has a value greater than or equal to May 25, 2006. The date is specified in the format MM/DD/YYYY, which is a valid format for SQL.

B. SELECT * FROM Contest GROUPBY ContestDate >= '05/25/2006': This option is incorrect because it contains a syntax error. The GROUP BY clause is used to group rows based on a certain criteria, not to filter them. Also, the condition is not valid in the GROUP BY clause.

C. SELECT * FROM Contest WHERE ContestDate < '05/25/2006': This option is incorrect because it selects all rows from the Contest table where the ContestDate column has a value less than May 25, 2006. The question asks for values greater than or equal to that date.

D. SELECT * FROM Contest HAVING ContestDate >= '05/25/2006': This option is incorrect because the HAVING clause is used to filter rows based on a condition that involves an aggregate function. It cannot be used to filter rows based on a simple comparison like the one specified in this question.

The Answer is: A