Concepts and Architecture Question:
What is high watermark in oracle?
Answer:
1. High water mark is the maximum amount of database blocks used so far by a segment. This mark cannot be reset by delete operations.
2. Delete Table operation wont reset HWM.
3. TRUNCATE will reset HWM.
4. The high water mark level is just a line separate the used blocks and free blocks.
The blocks above the HWM level is free blocks, they are ready to use.
The blocks below the HWM level is used blocks, they are already used.
2. Delete Table operation wont reset HWM.
3. TRUNCATE will reset HWM.
4. The high water mark level is just a line separate the used blocks and free blocks.
The blocks above the HWM level is free blocks, they are ready to use.
The blocks below the HWM level is used blocks, they are already used.
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