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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2002-07-31 17:19:54 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2002-07-31 17:19:54 +0000 |
| commit | ce7565ab91100747d250ef67d72af5c1b01150d4 (patch) | |
| tree | 968d1af6054a60d13e292d786c2f695da02b2a9d /src/backend/commands/analyze.c | |
| parent | 8be3cfbbd5e9afaa77a86251566d3ca04217fcb2 (diff) | |
| download | postgresql-ce7565ab91100747d250ef67d72af5c1b01150d4.tar.gz postgresql-ce7565ab91100747d250ef67d72af5c1b01150d4.zip | |
Instead of having a configure-time DEFAULT_ATTSTATTARGET, store -1 in
attstattarget to indicate 'use the default'. The default is now a GUC
variable default_statistics_target, and so may be changed on the fly. Along
the way we gain the ability to have pg_dump dump the per-column statistics
target when it's not the default. Patch by Neil Conway, with some kibitzing
from Tom Lane.
Diffstat (limited to 'src/backend/commands/analyze.c')
| -rw-r--r-- | src/backend/commands/analyze.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c index 6caa968b5d2..55069aa6feb 100644 --- a/src/backend/commands/analyze.c +++ b/src/backend/commands/analyze.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/commands/analyze.c,v 1.38 2002/06/20 20:29:26 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/commands/analyze.c,v 1.39 2002/07/31 17:19:51 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -107,6 +107,11 @@ typedef struct #define swapInt(a,b) do {int _tmp; _tmp=a; a=b; b=_tmp;} while(0) #define swapDatum(a,b) do {Datum _tmp; _tmp=a; a=b; b=_tmp;} while(0) + +/* Default statistics target (GUC parameter) */ +int default_statistics_target = 10; + + static int elevel = -1; static MemoryContext anl_context = NULL; @@ -384,7 +389,7 @@ examine_attribute(Relation onerel, int attnum) VacAttrStats *stats; /* Don't analyze column if user has specified not to */ - if (attr->attstattarget <= 0) + if (attr->attstattarget == 0) return NULL; /* If column has no "=" operator, we can't do much of anything */ @@ -425,6 +430,10 @@ examine_attribute(Relation onerel, int attnum) stats->eqopr = eqopr; stats->eqfunc = eqfunc; + /* If the attstattarget column is negative, use the default value */ + if (stats->attr->attstattarget < 0) + stats->attr->attstattarget = default_statistics_target; + /* Is there a "<" operator with suitable semantics? */ func_operator = compatible_oper(makeList1(makeString("<")), attr->atttypid, @@ -466,14 +475,14 @@ examine_attribute(Relation onerel, int attnum) * know it at this point. *-------------------- */ - stats->minrows = 300 * attr->attstattarget; + stats->minrows = 300 * stats->attr->attstattarget; } else { /* Can't do much but the minimal stuff */ stats->algcode = ALG_MINIMAL; /* Might as well use the same minrows as above */ - stats->minrows = 300 * attr->attstattarget; + stats->minrows = 300 * stats->attr->attstattarget; } return stats; |