What is difference between UNIQUE constraint and

Interview Questions

What is difference between UNIQUE constraint and PRIMARY KEY constraint?

DATABASE Administrator (DBA) Interview Questions and Answers

35. What is difference between UNIQUE constraint and PRIMARY KEY constraint?

A column defined as UNIQUE can contain Nulls while a column defined as PRIMARY KEY can’t contain Nulls. 47.What is Index Cluster? - A Cluster with an index on the Cluster Key 48.When does a Transaction end? - When it is committed or Rollbacked.

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What are the built-ins that are used to Attach an LOV programmatically to an item?
How do you call other Oracle Products from Oracle Forms?
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What are the different types of Record Groups?
From which designation is it preferred to send the output to the printed?
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Which of the above methods is the faster method?
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If the maximum record retrieved property of the query is set to 10 then a summary value will be calculated?
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What are the master-detail triggers?
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What is an OLE?
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Can a repeating frame be created without a data group as a base?
If a break order is set on a column would it affect columns which are under the column?
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What are the different default triggers created when Master Deletes Property is set to isolated?
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What use of command line parameter cmd file?
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What are built-ins used for Processing rows?
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What are the built-ins used for Getting cell values?
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What is the remove on exit property?
What is WHEN-Database-record trigger?
What is a difference between pre-select and pre-query?
What are built-ins associated with timers?
What are the built-ins used for finding object ID functions?
What are the built-ins used for finding Object ID function?
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What are the various sub events a mouse double click event involves?
How can a break order be created on a column in an existing group?
What is the use of place holder column?
What is the use of hidden column?
What is the use of break group?
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What are the default parameter that appear at run time in the parameter screen?
What are the built-ins used for Creating and deleting groups?
What are different types of canvas views?
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What is a Query Record Group?
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What does the term panel refer to with regarda to pages?
What is a master detail relationship?
What is a library?
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What are the various methods of performing a calculation in a report?
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How can you find out how many users are currently logged into the database? How can you find their operating system id?
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How do you set up tablespaces during an Oracle installation?
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What are some indications that you need to increase the SHARED_POOL_SIZE parameter?
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What is the fastest query method for a table?
Explain the use of TKPROF? What initialization parameter should be turned on to get full TKPROF output?
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Discuss row chaining, how does it happen? How can you reduce it? How do you correct it?
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If you see statistics that deal with "undo" what are they really talking about?
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