From 83e176ec18d2a91dbea1d0d1bd94c38dc47cd77c Mon Sep 17 00:00:00 2001 From: Simon Riggs Date: Fri, 15 May 2015 04:02:54 +0200 Subject: Separate block sampling functions Refactoring ahead of tablesample patch Requested and reviewed by Michael Paquier Petr Jelinek --- contrib/postgres_fdw/postgres_fdw.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'contrib/postgres_fdw/postgres_fdw.c') diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 4f7123b84f4..43288c27b02 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -37,6 +37,7 @@ #include "utils/lsyscache.h" #include "utils/memutils.h" #include "utils/rel.h" +#include "utils/sampling.h" PG_MODULE_MAGIC; @@ -202,7 +203,7 @@ typedef struct PgFdwAnalyzeState /* for random sampling */ double samplerows; /* # of rows fetched */ double rowstoskip; /* # of rows to skip before next sample */ - double rstate; /* random state */ + ReservoirStateData rstate; /* state for reservoir sampling*/ /* working memory contexts */ MemoryContext anl_cxt; /* context for per-analyze lifespan data */ @@ -2411,7 +2412,7 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel, astate.numrows = 0; astate.samplerows = 0; astate.rowstoskip = -1; /* -1 means not set yet */ - astate.rstate = anl_init_selection_state(targrows); + reservoir_init_selection_state(&astate.rstate, targrows); /* Remember ANALYZE context, and create a per-tuple temp context */ astate.anl_cxt = CurrentMemoryContext; @@ -2551,13 +2552,12 @@ analyze_row_processor(PGresult *res, int row, PgFdwAnalyzeState *astate) * analyze.c; see Jeff Vitter's paper. */ if (astate->rowstoskip < 0) - astate->rowstoskip = anl_get_next_S(astate->samplerows, targrows, - &astate->rstate); + astate->rowstoskip = reservoir_get_next_S(&astate->rstate, astate->samplerows, targrows); if (astate->rowstoskip <= 0) { /* Choose a random reservoir element to replace. */ - pos = (int) (targrows * anl_random_fract()); + pos = (int) (targrows * sampler_random_fract()); Assert(pos >= 0 && pos < targrows); heap_freetuple(astate->rows[pos]); } -- cgit v1.2.3