ORACLE INTERVIEW QUESTION & ANSWERS
| 91. |
What is a cluster? |
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Cluster are used to store multiple indexes of frequently joined tables
into a single, physical object. |
| 92. |
What are the types of partitions? |
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There are five different types of partitions as follows are - Range : Divides up rows based on ranges of values.
- Values List : Divides up rows based on sets of literal values.
- Hash : Uses a hashing algorithm to divide rows, resulting in the most consistently sized partitions.
- Composite Partitions : Contains subpartitions within each separate partition : Range–Hash : A range partition containing hash subpartitions within each range partition.
Range–List : A range partition containing list value subpartitions within each range partition. |
| 93. |
What are the types of Partition Indexing? |
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Partitions can have indexes. There are two types of partition index are : - Local Index
- Global Index
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| 94. |
What is a view? |
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- A view is a query that is stored in the database and executed to create a virtual table.
- Views do not contain any data of their own, and therefore do not require storage.
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| 95. |
What is the use of view? |
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- It can be used to hide sensitive columns.
- It can be used to hide complex queries involving multiple tables.
- Views provide data in a different perspective than that of a base table by renaming columns without affecting the base table.
- Views created with a check option, prevents die updating of other rows and columns.
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