SQL INTERVIEW QUESTION & ANSWERS
31. |
What is forms server? |
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The forms server is that server from which the forms are hosted.
It’s a component of middle tier. The forms server can be hosted from more than one node and the load balancing can be implemented with the forms. The forms user interface is used in the desktop clients for working in Oracle Applications.
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32. |
What does the application tier consist of? |
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The application tier is the place where the application software is located. It also hosts a large number of servers which interact with the database and the client tier. The application tier architecture shifts software administration from the desktop to the middle tier removing the burden of installing the application software at every client. The application tier also supports load
balancing among multiple forms server, concurrent processing server to provide optimum scalability and performance.
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33. |
What is not null constraint? |
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The not null constraint ensures that the users always type the value for that column or column becomes a mandatory column. Not null constraint can be applied at column level only.
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34. |
What is primary key? |
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Primary key is used to uniquely identify each row of the table. A table can have only one primary key.
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Posted by Aziz. (Jan 23, 2014) |
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Oracle implicitly create unique index when primary key is define. Primary key define at table level and also column level. |
35. |
What is check constraint? |
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Check constraint ensure that when data is entered, the data in the column is limited to specific values. |