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First cut at making indexscan cost estimates depend on correlation
between index order and table order.
This commit is contained in:
Tom Lane
parent
e02033572d
commit
c23bc6fbb0
@ -1,5 +1,5 @@
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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/indexcost.sgml,v 2.6 2000/12/22 21:51:57 petere Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/Attic/indexcost.sgml,v 2.7 2001/05/09 23:13:34 tgl Exp $
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-->
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<chapter id="indexcost">
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@ -57,7 +57,8 @@ amcostestimate (Query *root,
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List *indexQuals,
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Cost *indexStartupCost,
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Cost *indexTotalCost,
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Selectivity *indexSelectivity);
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Selectivity *indexSelectivity,
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double *indexCorrelation);
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</programlisting>
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The first four parameters are inputs:
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@ -103,7 +104,7 @@ amcostestimate (Query *root,
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</para>
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<para>
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The last three parameters are pass-by-reference outputs:
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The last four parameters are pass-by-reference outputs:
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<variablelist>
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<varlistentry>
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@ -132,6 +133,16 @@ amcostestimate (Query *root,
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>*indexCorrelation</term>
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<listitem>
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<para>
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Set to correlation coefficient between index scan order and
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underlying table's order
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</para>
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@ -172,6 +183,13 @@ amcostestimate (Query *root,
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tuples that actually pass the given qual conditions.
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</para>
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<para>
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The indexCorrelation should be set to the correlation (ranging between
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-1.0 and 1.0) between the index order and the table order. This is used
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to adjust the estimate for the cost of fetching tuples from the main
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table.
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</para>
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<procedure>
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<title>Cost Estimation</title>
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<para>
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@ -224,6 +242,14 @@ amcostestimate (Query *root,
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</programlisting>
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</para>
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</step>
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<step>
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<para>
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Estimate the index correlation. For a simple ordered index on a single
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field, this can be retrieved from pg_statistic. If the correlation
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is not known, the conservative estimate is zero (no correlation).
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</para>
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</step>
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</procedure>
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<para>
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@ -237,8 +263,8 @@ amcostestimate (Query *root,
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<programlisting>
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prorettype = 0
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pronargs = 7
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proargtypes = 0 0 0 0 0 0 0
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pronargs = 8
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proargtypes = 0 0 0 0 0 0 0 0
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</programlisting>
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We use zero ("opaque") for all the arguments since none of them have types
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@ -31,17 +31,18 @@
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* result by interpolating between startup_cost and total_cost. In detail:
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* actual_cost = startup_cost +
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* (total_cost - startup_cost) * tuples_to_fetch / path->parent->rows;
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* Note that a relation's rows count (and, by extension, a Plan's plan_rows)
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* are set without regard to any LIMIT, so that this equation works properly.
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* (Also, these routines guarantee not to set the rows count to zero, so there
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* will be no zero divide.) The LIMIT is applied as a separate Plan node.
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* Note that a base relation's rows count (and, by extension, plan_rows for
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* plan nodes below the LIMIT node) are set without regard to any LIMIT, so
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* that this equation works properly. (Also, these routines guarantee not to
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* set the rows count to zero, so there will be no zero divide.) The LIMIT is
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* applied as a top-level plan node.
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*
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*
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.72 2001/05/09 00:35:09 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/costsize.c,v 1.73 2001/05/09 23:13:34 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -205,12 +206,18 @@ cost_index(Path *path, Query *root,
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{
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Cost startup_cost = 0;
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Cost run_cost = 0;
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Cost cpu_per_tuple;
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Cost indexStartupCost;
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Cost indexTotalCost;
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Selectivity indexSelectivity;
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double indexCorrelation,
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csquared;
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Cost min_IO_cost,
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max_IO_cost;
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Cost cpu_per_tuple;
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double tuples_fetched;
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double pages_fetched;
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double T,
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b;
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/* Should only be applied to base relations */
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Assert(IsA(baserel, RelOptInfo) &&IsA(index, IndexOptInfo));
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@ -224,38 +231,52 @@ cost_index(Path *path, Query *root,
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* Call index-access-method-specific code to estimate the processing
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* cost for scanning the index, as well as the selectivity of the
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* index (ie, the fraction of main-table tuples we will have to
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* retrieve).
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* retrieve) and its correlation to the main-table tuple order.
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*/
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OidFunctionCall7(index->amcostestimate,
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OidFunctionCall8(index->amcostestimate,
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PointerGetDatum(root),
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PointerGetDatum(baserel),
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PointerGetDatum(index),
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PointerGetDatum(indexQuals),
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PointerGetDatum(&indexStartupCost),
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PointerGetDatum(&indexTotalCost),
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PointerGetDatum(&indexSelectivity));
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PointerGetDatum(&indexSelectivity),
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PointerGetDatum(&indexCorrelation));
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/* all costs for touching index itself included here */
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startup_cost += indexStartupCost;
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run_cost += indexTotalCost - indexStartupCost;
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/*
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/*----------
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* Estimate number of main-table tuples and pages fetched.
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*
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* If the number of tuples is much smaller than the number of pages in
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* the relation, each tuple will cost a separate nonsequential fetch.
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* If it is comparable or larger, then probably we will be able to
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* avoid some fetches. We use a growth rate of log(#tuples/#pages +
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* 1) --- probably totally bogus, but intuitively it gives the right
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* shape of curve at least.
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* When the index ordering is uncorrelated with the table ordering,
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* we use an approximation proposed by Mackert and Lohman, "Index Scans
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* Using a Finite LRU Buffer: A Validated I/O Model", ACM Transactions
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* on Database Systems, Vol. 14, No. 3, September 1989, Pages 401-424.
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* The Mackert and Lohman approximation is that the number of pages
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* fetched is
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* PF =
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* min(2TNs/(2T+Ns), T) when T <= b
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* 2TNs/(2T+Ns) when T > b and Ns <= 2Tb/(2T-b)
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* b + (Ns - 2Tb/(2T-b))*(T-b)/T when T > b and Ns > 2Tb/(2T-b)
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* where
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* T = # pages in table
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* N = # tuples in table
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* s = selectivity = fraction of table to be scanned
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* b = # buffer pages available (we include kernel space here)
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*
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* XXX if the relation has recently been "clustered" using this index,
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* then in fact the target tuples will be highly nonuniformly
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* distributed, and we will be seriously overestimating the scan cost!
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* Currently we have no way to know whether the relation has been
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* clustered, nor how much it's been modified since the last
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* clustering, so we ignore this effect. Would be nice to do better
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* someday.
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* When the index ordering is exactly correlated with the table ordering
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* (just after a CLUSTER, for example), the number of pages fetched should
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* be just sT. What's more, these will be sequential fetches, not the
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* random fetches that occur in the uncorrelated case. So, depending on
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* the extent of correlation, we should estimate the actual I/O cost
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* somewhere between s * T * 1.0 and PF * random_cost. We currently
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* interpolate linearly between these two endpoints based on the
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* correlation squared (XXX is that appropriate?).
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*
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* In any case the number of tuples fetched is Ns.
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*----------
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*/
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tuples_fetched = indexSelectivity * baserel->tuples;
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@ -263,24 +284,56 @@ cost_index(Path *path, Query *root,
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if (tuples_fetched < 1.0)
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tuples_fetched = 1.0;
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if (baserel->pages > 0)
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pages_fetched = ceil(baserel->pages *
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log(tuples_fetched / baserel->pages + 1.0));
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/* This part is the Mackert and Lohman formula */
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T = (baserel->pages > 1) ? (double) baserel->pages : 1.0;
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b = (effective_cache_size > 1) ? effective_cache_size : 1.0;
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if (T <= b)
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{
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pages_fetched =
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(2.0 * T * tuples_fetched) / (2.0 * T + tuples_fetched);
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if (pages_fetched > T)
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pages_fetched = T;
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}
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else
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pages_fetched = tuples_fetched;
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{
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double lim;
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lim = (2.0 * T * b) / (2.0 * T - b);
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if (tuples_fetched <= lim)
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{
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pages_fetched =
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(2.0 * T * tuples_fetched) / (2.0 * T + tuples_fetched);
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}
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else
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{
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pages_fetched =
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b + (tuples_fetched - lim) * (T - b) / T;
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}
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}
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/*
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* Now estimate one nonsequential access per page fetched, plus
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* appropriate CPU costs per tuple.
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* min_IO_cost corresponds to the perfectly correlated case (csquared=1),
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* max_IO_cost to the perfectly uncorrelated case (csquared=0). Note
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* that we just charge random_page_cost per page in the uncorrelated
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* case, rather than using cost_nonsequential_access, since we've already
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* accounted for caching effects by using the Mackert model.
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*/
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/* disk costs for main table */
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run_cost += pages_fetched * cost_nonsequential_access(baserel->pages);
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/* CPU costs */
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cpu_per_tuple = cpu_tuple_cost + baserel->baserestrictcost;
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min_IO_cost = ceil(indexSelectivity * T);
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max_IO_cost = pages_fetched * random_page_cost;
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/*
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* Now interpolate based on estimated index order correlation
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* to get total disk I/O cost for main table accesses.
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*/
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csquared = indexCorrelation * indexCorrelation;
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run_cost += max_IO_cost + csquared * (min_IO_cost - max_IO_cost);
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/*
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* Estimate CPU costs per tuple.
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*
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* Normally the indexquals will be removed from the list of
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* restriction clauses that we have to evaluate as qpquals, so we
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* should subtract their costs from baserestrictcost. For a lossy
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@ -290,6 +343,8 @@ cost_index(Path *path, Query *root,
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* Rather than work out exactly how much to subtract, we don't
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* subtract anything in that case either.
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*/
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cpu_per_tuple = cpu_tuple_cost + baserel->baserestrictcost;
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if (!index->lossy && !is_injoin)
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cpu_per_tuple -= cost_qual_eval(indexQuals);
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/optimizer/util/var.c,v 1.31 2001/04/18 20:42:55 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/optimizer/util/var.c,v 1.32 2001/05/09 23:13:35 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -28,8 +28,9 @@ typedef struct
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typedef struct
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{
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int varno;
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int varattno;
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int sublevels_up;
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} contain_whole_tuple_var_context;
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} contain_var_reference_context;
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typedef struct
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{
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@ -39,8 +40,8 @@ typedef struct
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static bool pull_varnos_walker(Node *node,
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pull_varnos_context *context);
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static bool contain_whole_tuple_var_walker(Node *node,
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contain_whole_tuple_var_context *context);
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static bool contain_var_reference_walker(Node *node,
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contain_var_reference_context *context);
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static bool contain_var_clause_walker(Node *node, void *context);
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static bool pull_var_clause_walker(Node *node,
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pull_var_clause_context *context);
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@ -129,10 +130,10 @@ pull_varnos_walker(Node *node, pull_varnos_context *context)
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/*
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* contain_whole_tuple_var
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* contain_var_reference
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*
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* Detect whether a parsetree contains any references to the whole
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* tuple of a given rtable entry (ie, a Var with varattno = 0).
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* Detect whether a parsetree contains any references to a specified
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* attribute of a specified rtable entry.
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*
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* NOTE: this is used on not-yet-planned expressions. It may therefore find
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* bare SubLinks, and if so it needs to recurse into them to look for uplevel
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@ -140,11 +141,12 @@ pull_varnos_walker(Node *node, pull_varnos_context *context)
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* SubPlan, we only need to look at the parameters passed to the subplan.
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*/
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bool
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contain_whole_tuple_var(Node *node, int varno, int levelsup)
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contain_var_reference(Node *node, int varno, int varattno, int levelsup)
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{
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contain_whole_tuple_var_context context;
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contain_var_reference_context context;
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context.varno = varno;
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context.varattno = varattno;
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context.sublevels_up = levelsup;
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/*
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@ -154,15 +156,15 @@ contain_whole_tuple_var(Node *node, int varno, int levelsup)
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*/
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if (node && IsA(node, Query))
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return query_tree_walker((Query *) node,
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contain_whole_tuple_var_walker,
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contain_var_reference_walker,
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(void *) &context, true);
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else
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return contain_whole_tuple_var_walker(node, &context);
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return contain_var_reference_walker(node, &context);
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}
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static bool
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contain_whole_tuple_var_walker(Node *node,
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contain_whole_tuple_var_context *context)
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contain_var_reference_walker(Node *node,
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contain_var_reference_context *context)
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{
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if (node == NULL)
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return false;
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@ -171,8 +173,8 @@ contain_whole_tuple_var_walker(Node *node,
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Var *var = (Var *) node;
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if (var->varno == context->varno &&
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var->varlevelsup == context->sublevels_up &&
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var->varattno == InvalidAttrNumber)
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var->varattno == context->varattno &&
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var->varlevelsup == context->sublevels_up)
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return true;
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return false;
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}
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@ -187,11 +189,11 @@ contain_whole_tuple_var_walker(Node *node,
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*/
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Expr *expr = (Expr *) node;
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if (contain_whole_tuple_var_walker((Node *) ((SubPlan *) expr->oper)->sublink->oper,
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context))
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if (contain_var_reference_walker((Node *) ((SubPlan *) expr->oper)->sublink->oper,
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context))
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return true;
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if (contain_whole_tuple_var_walker((Node *) expr->args,
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context))
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if (contain_var_reference_walker((Node *) expr->args,
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context))
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return true;
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return false;
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}
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@ -202,16 +204,29 @@ contain_whole_tuple_var_walker(Node *node,
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context->sublevels_up++;
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result = query_tree_walker((Query *) node,
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contain_whole_tuple_var_walker,
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contain_var_reference_walker,
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(void *) context, true);
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context->sublevels_up--;
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return result;
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}
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return expression_tree_walker(node, contain_whole_tuple_var_walker,
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return expression_tree_walker(node, contain_var_reference_walker,
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(void *) context);
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}
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/*
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* contain_whole_tuple_var
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*
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* Detect whether a parsetree contains any references to the whole
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* tuple of a given rtable entry (ie, a Var with varattno = 0).
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*/
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bool
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contain_whole_tuple_var(Node *node, int varno, int levelsup)
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{
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return contain_var_reference(node, varno, InvalidAttrNumber, levelsup);
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}
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/*
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* contain_var_clause
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* Recursively scan a clause to discover whether it contains any Var nodes
|
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@ -15,7 +15,7 @@
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*
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*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.88 2001/05/07 00:43:23 tgl Exp $
|
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.89 2001/05/09 23:13:35 tgl Exp $
|
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*
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*-------------------------------------------------------------------------
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*/
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@ -39,6 +39,7 @@
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#include "optimizer/cost.h"
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#include "parser/parse_func.h"
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#include "parser/parse_oper.h"
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#include "parser/parsetree.h"
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#include "utils/builtins.h"
|
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#include "utils/date.h"
|
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#include "utils/int8.h"
|
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@ -818,7 +819,6 @@ eqjoinsel(PG_FUNCTION_ARGS)
|
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{
|
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#ifdef NOT_USED /* see neqjoinsel() before removing me! */
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Oid opid = PG_GETARG_OID(0);
|
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|
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#endif
|
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Oid relid1 = PG_GETARG_OID(1);
|
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AttrNumber attno1 = PG_GETARG_INT16(2);
|
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@ -2230,16 +2230,14 @@ string_to_datum(const char *str, Oid datatype)
|
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*-------------------------------------------------------------------------
|
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*/
|
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|
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static Datum
|
||||
genericcostestimate(PG_FUNCTION_ARGS)
|
||||
static void
|
||||
genericcostestimate(Query *root, RelOptInfo *rel,
|
||||
IndexOptInfo *index, List *indexQuals,
|
||||
Cost *indexStartupCost,
|
||||
Cost *indexTotalCost,
|
||||
Selectivity *indexSelectivity,
|
||||
double *indexCorrelation)
|
||||
{
|
||||
Query *root = (Query *) PG_GETARG_POINTER(0);
|
||||
RelOptInfo *rel = (RelOptInfo *) PG_GETARG_POINTER(1);
|
||||
IndexOptInfo *index = (IndexOptInfo *) PG_GETARG_POINTER(2);
|
||||
List *indexQuals = (List *) PG_GETARG_POINTER(3);
|
||||
Cost *indexStartupCost = (Cost *) PG_GETARG_POINTER(4);
|
||||
Cost *indexTotalCost = (Cost *) PG_GETARG_POINTER(5);
|
||||
Selectivity *indexSelectivity = (Selectivity *) PG_GETARG_POINTER(6);
|
||||
double numIndexTuples;
|
||||
double numIndexPages;
|
||||
|
||||
@ -2275,33 +2273,134 @@ genericcostestimate(PG_FUNCTION_ARGS)
|
||||
*indexTotalCost = numIndexPages +
|
||||
(cpu_index_tuple_cost + cost_qual_eval(indexQuals)) * numIndexTuples;
|
||||
|
||||
PG_RETURN_VOID();
|
||||
/*
|
||||
* Generic assumption about index correlation: there isn't any.
|
||||
*/
|
||||
*indexCorrelation = 0.0;
|
||||
}
|
||||
|
||||
/*
|
||||
* For first cut, just use generic function for all index types.
|
||||
*/
|
||||
|
||||
Datum
|
||||
btcostestimate(PG_FUNCTION_ARGS)
|
||||
{
|
||||
return genericcostestimate(fcinfo);
|
||||
Query *root = (Query *) PG_GETARG_POINTER(0);
|
||||
RelOptInfo *rel = (RelOptInfo *) PG_GETARG_POINTER(1);
|
||||
IndexOptInfo *index = (IndexOptInfo *) PG_GETARG_POINTER(2);
|
||||
List *indexQuals = (List *) PG_GETARG_POINTER(3);
|
||||
Cost *indexStartupCost = (Cost *) PG_GETARG_POINTER(4);
|
||||
Cost *indexTotalCost = (Cost *) PG_GETARG_POINTER(5);
|
||||
Selectivity *indexSelectivity = (Selectivity *) PG_GETARG_POINTER(6);
|
||||
double *indexCorrelation = (double *) PG_GETARG_POINTER(7);
|
||||
|
||||
genericcostestimate(root, rel, index, indexQuals,
|
||||
indexStartupCost, indexTotalCost,
|
||||
indexSelectivity, indexCorrelation);
|
||||
|
||||
/*
|
||||
* If it's a functional index, leave the default zero-correlation
|
||||
* estimate in place. If not, and if we can get an estimate for
|
||||
* the first variable's ordering correlation C from pg_statistic,
|
||||
* estimate the index correlation as C / number-of-columns.
|
||||
* (The idea here is that multiple columns dilute the importance
|
||||
* of the first column's ordering, but don't negate it entirely.)
|
||||
*/
|
||||
if (index->indproc == InvalidOid)
|
||||
{
|
||||
Oid relid;
|
||||
HeapTuple tuple;
|
||||
|
||||
relid = getrelid(lfirsti(rel->relids), root->rtable);
|
||||
Assert(relid != InvalidOid);
|
||||
tuple = SearchSysCache(STATRELATT,
|
||||
ObjectIdGetDatum(relid),
|
||||
Int16GetDatum(index->indexkeys[0]),
|
||||
0, 0);
|
||||
if (HeapTupleIsValid(tuple))
|
||||
{
|
||||
Oid typid;
|
||||
int32 typmod;
|
||||
float4 *numbers;
|
||||
int nnumbers;
|
||||
|
||||
get_atttypetypmod(relid, index->indexkeys[0],
|
||||
&typid, &typmod);
|
||||
if (get_attstatsslot(tuple, typid, typmod,
|
||||
STATISTIC_KIND_CORRELATION,
|
||||
index->ordering[0],
|
||||
NULL, NULL, &numbers, &nnumbers))
|
||||
{
|
||||
double varCorrelation;
|
||||
int nKeys;
|
||||
|
||||
Assert(nnumbers == 1);
|
||||
varCorrelation = numbers[0];
|
||||
for (nKeys = 1; index->indexkeys[nKeys] != 0; nKeys++)
|
||||
/*skip*/;
|
||||
|
||||
*indexCorrelation = varCorrelation / nKeys;
|
||||
|
||||
free_attstatsslot(typid, NULL, 0, numbers, nnumbers);
|
||||
}
|
||||
ReleaseSysCache(tuple);
|
||||
}
|
||||
}
|
||||
|
||||
PG_RETURN_VOID();
|
||||
}
|
||||
|
||||
Datum
|
||||
rtcostestimate(PG_FUNCTION_ARGS)
|
||||
{
|
||||
return genericcostestimate(fcinfo);
|
||||
Query *root = (Query *) PG_GETARG_POINTER(0);
|
||||
RelOptInfo *rel = (RelOptInfo *) PG_GETARG_POINTER(1);
|
||||
IndexOptInfo *index = (IndexOptInfo *) PG_GETARG_POINTER(2);
|
||||
List *indexQuals = (List *) PG_GETARG_POINTER(3);
|
||||
Cost *indexStartupCost = (Cost *) PG_GETARG_POINTER(4);
|
||||
Cost *indexTotalCost = (Cost *) PG_GETARG_POINTER(5);
|
||||
Selectivity *indexSelectivity = (Selectivity *) PG_GETARG_POINTER(6);
|
||||
double *indexCorrelation = (double *) PG_GETARG_POINTER(7);
|
||||
|
||||
genericcostestimate(root, rel, index, indexQuals,
|
||||
indexStartupCost, indexTotalCost,
|
||||
indexSelectivity, indexCorrelation);
|
||||
|
||||
PG_RETURN_VOID();
|
||||
}
|
||||
|
||||
Datum
|
||||
hashcostestimate(PG_FUNCTION_ARGS)
|
||||
{
|
||||
return genericcostestimate(fcinfo);
|
||||
Query *root = (Query *) PG_GETARG_POINTER(0);
|
||||
RelOptInfo *rel = (RelOptInfo *) PG_GETARG_POINTER(1);
|
||||
IndexOptInfo *index = (IndexOptInfo *) PG_GETARG_POINTER(2);
|
||||
List *indexQuals = (List *) PG_GETARG_POINTER(3);
|
||||
Cost *indexStartupCost = (Cost *) PG_GETARG_POINTER(4);
|
||||
Cost *indexTotalCost = (Cost *) PG_GETARG_POINTER(5);
|
||||
Selectivity *indexSelectivity = (Selectivity *) PG_GETARG_POINTER(6);
|
||||
double *indexCorrelation = (double *) PG_GETARG_POINTER(7);
|
||||
|
||||
genericcostestimate(root, rel, index, indexQuals,
|
||||
indexStartupCost, indexTotalCost,
|
||||
indexSelectivity, indexCorrelation);
|
||||
|
||||
PG_RETURN_VOID();
|
||||
}
|
||||
|
||||
Datum
|
||||
gistcostestimate(PG_FUNCTION_ARGS)
|
||||
{
|
||||
return genericcostestimate(fcinfo);
|
||||
Query *root = (Query *) PG_GETARG_POINTER(0);
|
||||
RelOptInfo *rel = (RelOptInfo *) PG_GETARG_POINTER(1);
|
||||
IndexOptInfo *index = (IndexOptInfo *) PG_GETARG_POINTER(2);
|
||||
List *indexQuals = (List *) PG_GETARG_POINTER(3);
|
||||
Cost *indexStartupCost = (Cost *) PG_GETARG_POINTER(4);
|
||||
Cost *indexTotalCost = (Cost *) PG_GETARG_POINTER(5);
|
||||
Selectivity *indexSelectivity = (Selectivity *) PG_GETARG_POINTER(6);
|
||||
double *indexCorrelation = (double *) PG_GETARG_POINTER(7);
|
||||
|
||||
genericcostestimate(root, rel, index, indexQuals,
|
||||
indexStartupCost, indexTotalCost,
|
||||
indexSelectivity, indexCorrelation);
|
||||
|
||||
PG_RETURN_VOID();
|
||||
}
|
||||
|
||||
32
src/backend/utils/cache/lsyscache.c
vendored
32
src/backend/utils/cache/lsyscache.c
vendored
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* IDENTIFICATION
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.54 2001/05/09 00:35:09 tgl Exp $
|
||||
* $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.55 2001/05/09 23:13:35 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* Eventually, the index information should go through here, too.
|
||||
@ -185,6 +185,36 @@ get_atttypmod(Oid relid, AttrNumber attnum)
|
||||
return -1;
|
||||
}
|
||||
|
||||
/*
|
||||
* get_atttypetypmod
|
||||
*
|
||||
* A two-fer: given the relation id and the attribute number,
|
||||
* fetch both type OID and atttypmod in a single cache lookup.
|
||||
*
|
||||
* Unlike the otherwise-similar get_atttype/get_atttypmod, this routine
|
||||
* raises an error if it can't obtain the information.
|
||||
*/
|
||||
void
|
||||
get_atttypetypmod(Oid relid, AttrNumber attnum,
|
||||
Oid *typid, int32 *typmod)
|
||||
{
|
||||
HeapTuple tp;
|
||||
Form_pg_attribute att_tup;
|
||||
|
||||
tp = SearchSysCache(ATTNUM,
|
||||
ObjectIdGetDatum(relid),
|
||||
Int16GetDatum(attnum),
|
||||
0, 0);
|
||||
if (!HeapTupleIsValid(tp))
|
||||
elog(ERROR, "cache lookup failed for relation %u attribute %d",
|
||||
relid, attnum);
|
||||
att_tup = (Form_pg_attribute) GETSTRUCT(tp);
|
||||
|
||||
*typid = att_tup->atttypid;
|
||||
*typmod = att_tup->atttypmod;
|
||||
ReleaseSysCache(tp);
|
||||
}
|
||||
|
||||
/* ---------- INDEX CACHE ---------- */
|
||||
|
||||
/* watch this space...
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: pg_proc.h,v 1.184 2001/03/22 04:00:39 momjian Exp $
|
||||
* $Id: pg_proc.h,v 1.185 2001/05/09 23:13:35 tgl Exp $
|
||||
*
|
||||
* NOTES
|
||||
* The script catalog/genbki.sh reads this file and generates .bki
|
||||
@ -210,9 +210,9 @@ DESCR("not equal");
|
||||
DATA(insert OID = 89 ( version PGUID 12 f t f t 0 f 25 "" 100 0 0 100 pgsql_version - ));
|
||||
DESCR("PostgreSQL version string");
|
||||
|
||||
DATA(insert OID = 1265 ( rtcostestimate PGUID 12 f t f t 7 f 0 "0 0 0 0 0 0 0" 100 0 0 100 rtcostestimate - ));
|
||||
DATA(insert OID = 1265 ( rtcostestimate PGUID 12 f t f t 8 f 0 "0 0 0 0 0 0 0 0" 100 0 0 100 rtcostestimate - ));
|
||||
DESCR("r-tree cost estimator");
|
||||
DATA(insert OID = 1268 ( btcostestimate PGUID 12 f t f t 7 f 0 "0 0 0 0 0 0 0" 100 0 0 100 btcostestimate - ));
|
||||
DATA(insert OID = 1268 ( btcostestimate PGUID 12 f t f t 8 f 0 "0 0 0 0 0 0 0 0" 100 0 0 100 btcostestimate - ));
|
||||
DESCR("btree cost estimator");
|
||||
|
||||
/* OIDS 100 - 199 */
|
||||
@ -789,7 +789,7 @@ DESCR("convert name to char()");
|
||||
DATA(insert OID = 409 ( name PGUID 12 f t t t 1 f 19 "1042" 100 0 0 100 bpchar_name - ));
|
||||
DESCR("convert char() to name");
|
||||
|
||||
DATA(insert OID = 438 ( hashcostestimate PGUID 12 f t f t 7 f 0 "0 0 0 0 0 0 0" 100 0 0 100 hashcostestimate - ));
|
||||
DATA(insert OID = 438 ( hashcostestimate PGUID 12 f t f t 8 f 0 "0 0 0 0 0 0 0 0" 100 0 0 100 hashcostestimate - ));
|
||||
DESCR("hash index cost estimator");
|
||||
|
||||
DATA(insert OID = 440 ( hashgettuple PGUID 12 f t f t 2 f 23 "0 0" 100 0 0 100 hashgettuple - ));
|
||||
@ -1014,7 +1014,7 @@ DESCR("larger of two");
|
||||
DATA(insert OID = 771 ( int2smaller PGUID 12 f t t t 2 f 21 "21 21" 100 0 0 100 int2smaller - ));
|
||||
DESCR("smaller of two");
|
||||
|
||||
DATA(insert OID = 772 ( gistcostestimate PGUID 12 f t f t 7 f 0 "0 0 0 0 0 0 0" 100 0 0 100 gistcostestimate - ));
|
||||
DATA(insert OID = 772 ( gistcostestimate PGUID 12 f t f t 8 f 0 "0 0 0 0 0 0 0 0" 100 0 0 100 gistcostestimate - ));
|
||||
DESCR("gist cost estimator");
|
||||
DATA(insert OID = 774 ( gistgettuple PGUID 12 f t f t 2 f 23 "0 0" 100 0 0 100 gistgettuple - ));
|
||||
DESCR("gist(internal)");
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: var.h,v 1.13 2001/04/18 20:42:55 tgl Exp $
|
||||
* $Id: var.h,v 1.14 2001/05/09 23:13:36 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -17,6 +17,8 @@
|
||||
#include "nodes/primnodes.h"
|
||||
|
||||
extern List *pull_varnos(Node *node);
|
||||
extern bool contain_var_reference(Node *node, int varno, int varattno,
|
||||
int levelsup);
|
||||
extern bool contain_whole_tuple_var(Node *node, int varno, int levelsup);
|
||||
extern bool contain_var_clause(Node *node);
|
||||
extern List *pull_var_clause(Node *node, bool includeUpperVars);
|
||||
|
||||
@ -6,7 +6,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: lsyscache.h,v 1.32 2001/05/09 00:35:09 tgl Exp $
|
||||
* $Id: lsyscache.h,v 1.33 2001/05/09 23:13:37 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -21,6 +21,8 @@ extern AttrNumber get_attnum(Oid relid, char *attname);
|
||||
extern Oid get_atttype(Oid relid, AttrNumber attnum);
|
||||
extern bool get_attisset(Oid relid, char *attname);
|
||||
extern int32 get_atttypmod(Oid relid, AttrNumber attnum);
|
||||
extern void get_atttypetypmod(Oid relid, AttrNumber attnum,
|
||||
Oid *typid, int32 *typmod);
|
||||
extern RegProcedure get_opcode(Oid opno);
|
||||
extern char *get_opname(Oid opno);
|
||||
extern bool op_mergejoinable(Oid opno, Oid ltype, Oid rtype,
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user