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Tweak indexscan cost estimation: round estimated # of tuples visited up
authorTom Lane <tgl@sss.pgh.pa.us>
Thu, 30 Mar 2000 00:53:30 +0000 (00:53 +0000)
committerTom Lane <tgl@sss.pgh.pa.us>
Thu, 30 Mar 2000 00:53:30 +0000 (00:53 +0000)
commite55985d3be4aed47c703674c735c124ff0b3c03c
tree4be5accd90a1c1561737d9297ab0df7eec74118c
parent341dc91820b3f80ae69a51f2780fd0d8afcb2c47
Tweak indexscan cost estimation: round estimated # of tuples visited up
to next integer.  Previously, if selectivity was small, we could compute
very tiny scan cost on the basis of estimating that only 0.001 tuple
would be fetched, which is silly.  This naturally led to some rather
silly plans...
src/backend/optimizer/path/costsize.c
src/backend/utils/adt/selfuncs.c