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Add proofreader's changes to docs.

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Fix misspelling of disbursion to dispersion.
This commit is contained in:
Bruce Momjian
2000-10-05 19:48:34 +00:00
parent 05e3d0ee86
commit b32685a999
62 changed files with 259 additions and 259 deletions
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36
src/backend/utils/cache/lsyscache.c vendored
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@ -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 1.45 2000/08/13 02:50:16 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.46 2000/10/05 19:48:29 momjian Exp $
*
* NOTES
* Eventually, the index information should go through here, too.
@ -168,9 +168,9 @@ get_atttypmod(Oid relid, AttrNumber attnum)
}
/*
* get_attdisbursion
* get_attdispersion
*
* Retrieve the disbursion statistic for an attribute,
* Retrieve the dispersion statistic for an attribute,
* or produce an estimate if no info is available.
*
* min_estimate is the minimum estimate to return if insufficient data
@ -180,11 +180,11 @@ get_atttypmod(Oid relid, AttrNumber attnum)
* estimating the number of tuples produced by an equijoin.)
*/
double
get_attdisbursion(Oid relid, AttrNumber attnum, double min_estimate)
get_attdispersion(Oid relid, AttrNumber attnum, double min_estimate)
{
HeapTuple atp;
Form_pg_attribute att_tup;
double disbursion;
double dispersion;
int32 ntuples;
atp = SearchSysCacheTuple(ATTNUM,
@ -194,18 +194,18 @@ get_attdisbursion(Oid relid, AttrNumber attnum, double min_estimate)
if (!HeapTupleIsValid(atp))
{
/* this should not happen */
elog(ERROR, "get_attdisbursion: no attribute tuple %u %d",
elog(ERROR, "get_attdispersion: no attribute tuple %u %d",
relid, attnum);
return min_estimate;
}
att_tup = (Form_pg_attribute) GETSTRUCT(atp);
disbursion = att_tup->attdisbursion;
if (disbursion > 0.0)
return disbursion; /* we have a specific estimate from VACUUM */
dispersion = att_tup->attdispersion;
if (dispersion > 0.0)
return dispersion; /* we have a specific estimate from VACUUM */
/*
* Special-case boolean columns: the disbursion of a boolean is highly
* Special-case boolean columns: the dispersion of a boolean is highly
* unlikely to be anywhere near 1/numtuples, instead it's probably
* more like 0.5.
*
@ -215,7 +215,7 @@ get_attdisbursion(Oid relid, AttrNumber attnum, double min_estimate)
return 0.5;
/*
* Disbursion is either 0 (no data available) or -1 (disbursion is
* Dispersion is either 0 (no data available) or -1 (dispersion is
* 1/numtuples). Either way, we need the relation size.
*/
@ -225,7 +225,7 @@ get_attdisbursion(Oid relid, AttrNumber attnum, double min_estimate)
if (!HeapTupleIsValid(atp))
{
/* this should not happen */
elog(ERROR, "get_attdisbursion: no relation tuple %u", relid);
elog(ERROR, "get_attdispersion: no relation tuple %u", relid);
return min_estimate;
}
@ -234,11 +234,11 @@ get_attdisbursion(Oid relid, AttrNumber attnum, double min_estimate)
if (ntuples == 0)
return min_estimate; /* no data available */
if (disbursion < 0.0) /* VACUUM thinks there are no duplicates */
if (dispersion < 0.0) /* VACUUM thinks there are no duplicates */
return 1.0 / (double) ntuples;
/*
* VACUUM ANALYZE does not compute disbursion for system attributes,
* VACUUM ANALYZE does not compute dispersion for system attributes,
* but some of them can reasonably be assumed unique anyway.
*/
if (attnum == ObjectIdAttributeNumber ||
@ -252,11 +252,11 @@ get_attdisbursion(Oid relid, AttrNumber attnum, double min_estimate)
* = 1/numtuples. This may produce unreasonably small estimates for
* large tables, so limit the estimate to no less than min_estimate.
*/
disbursion = 1.0 / (double) ntuples;
if (disbursion < min_estimate)
disbursion = min_estimate;
dispersion = 1.0 / (double) ntuples;
if (dispersion < min_estimate)
dispersion = min_estimate;
return disbursion;
return dispersion;
}
/* ---------- INDEX CACHE ---------- */