Buffer Pool Functions
Buffer manager interface:
Buffer ReadBuffer(Relation r, BlockNumber n)
- ensures nth page of file for relation
r is loaded
(may need to remove an existing unpinned page and read data from file)
- increments reference (pin) count and usage count for buffer
- returns index of loaded page in buffer pool (
Buffer value)
- assumes main fork, so no
ForkNumber required
Actually a special case of ReadBuffer_Common , which also handles
variations like different replacement strategy, forks, temp buffers, ...
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