SQL INTERVIEW QUESTION & ANSWERS
86. |
What type of actions can be performed by the triggered SQL statements? |
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The triggered SQL statements can take such actions as updating tables, deleting data, invoking procedures, or performing most tasks that you can perform with SQL statements. |
87. |
What are the different types of triggers? |
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- BEFORE Triggers
- AFTER Triggers
- INSTEAD OF
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88. |
What is Normalisation? |
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It is an essential part of database design. A good understanding of the semantic of data helps the designer to built efficient design using the concept of normalization. |
89. |
What are the advantages and disadvantages of Normalization? |
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There are several advantages of normalization as under :- Faster sorting and index creation.
- A larger number of clustered indexes.
- Narrower and more compact indexes.
- Fewer indexes per table, which improves the performance of INSERT, UPDATE, and DELETE statements.
- Fewer null values and less opportunity for inconsistency, which increase database compactness.
Beside the above benefits there are few disadvantages as well : - Increased amount of Normalization increases the amount of complexity of joins between tables and that hinders the performance.
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90. |
Which type of identifier permits spaces to be used as part of the name of an object? |
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A delimited identifier |