Oracle Dba Interview Question and Answers
| 21. |
What is Change Data Capture? |
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- CDC is a technique to capture changes in database tables.
- These changes are stored in special tables.
- CDC operates in two modes asynchronous, which is based on Java, and synchronous, which is based on database triggers.
- Performance overhead is higher in case of synchronous CDC.
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| 22. |
What is log switch? |
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A log switch is a point when loG WRiter (LGWR)fills one online redo log group and writing to another.At every log switch a checkpoint,occurs.
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| 23. |
What is logical backup? |
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Logical backup is a process of extracting data in the form of SQL statements, where it is useful to recover in case the objects are lost. The main drawback of using this backup is that MEAN TIME TO RECOVER is high. |
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| 24. |
What is Global Resource Directory (GRD)? |
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GRD is used by GES and GCS to maintain status of datefiles and cached blocks. This process provides required information for cache fusion and maintains data integrity. |
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| 25. |
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. Form 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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Gk Questions with Answers