Database-Oracle (3i Infotech Papers): Sample Questions 1 - 2 of 132
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Question number: 1
» Database » Oracle
Question
Can an Integrity Constraint be enforced on a table if some existing table data does not satisfy the constraint?
Choices
| Choice (4) | Response | |
|---|---|---|
| a. | No |
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| b. | Yes |
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| c. | None of the above |
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| d. | Question does not provide sufficient data or is vague |
|
Answer
a.Explanation
Overview of Integrity Constraints.
Overview of integrity constraints.
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No, an integrity cannot Constraint cannot be enforced on a table if some existing table data does not satisfy the constraint.
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Integrity constrain are used to accuracy and consistency of data in a rational database.
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Data integrity is handled in a relational database using referential integrity.
Below the types of integrity constrains:
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UNIQUE
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To sure about a given column is unique
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NOT NULL
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To sure about that no null values are allowed
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FOREIGN KEY
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To sure two keys share a primary key to foreign key relationship.
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The Types of Integrity Constrains
The types of integrity constrains
Question number: 2
» Database » Oracle
Question
POST-BLOCK trigger is a….
Choices
| Choice (4) | Response | |
|---|---|---|
| a. | Transactional trigger |
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| b. | Key trigger |
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| c. | Navigational trigger |
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| d. | All of the above |
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Answer
c.Explanation
Example of Post-Block Trigger
Example of post-block trigger
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A navigational trigger
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Fires when the focus moves off the current block.
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Used to bring block’s current record, to a condition or to prevent the user from leaving a block based on condition.
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Form is set to put the cursor a particular block.
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Form builder attempts to put the cursor at a target location, if the target is outside of the current unit.
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Does not fire when the validation unit form document property it is set to form.