Fix confusion about data type of pg_class.relpages and relallvisible.

Although they're exposed as int4 in pg_class, relpages and
relallvisible are really of type BlockNumber, that is uint32.
Correct type puns in relation_statistics_update() and remove
inappropriate range-checks.  The type puns are only cosmetic
issues, but the range checks would cause failures with huge
relations.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/614341.1740269035@sss.pgh.pa.us

diff --git a/src/backend/statistics/relation_stats.c b/src/backend/statistics/relation_stats.c
index 046661d7c3ff691143920d545279a028808bd1b1..1f6c5c39121c9d761669eb7fd8d53f607ac077ed 100644 (file)
--- a/src/backend/statistics/relation_stats.c
+++ b/src/backend/statistics/relation_stats.c
@@ -24,9 +24,6 @@
 #include "utils/fmgrprotos.h"
 #include "utils/syscache.h"
 
-#define DEFAULT_RELPAGES Int32GetDatum(0)
-#define DEFAULT_RELTUPLES Float4GetDatum(-1.0)
-#define DEFAULT_RELALLVISIBLE Int32GetDatum(0)
 
 /*
  * Positional argument numbers, names, and types for
@@ -60,40 +57,25 @@ static bool relation_statistics_update(FunctionCallInfo fcinfo, int elevel,
 static bool
 relation_statistics_update(FunctionCallInfo fcinfo, int elevel, bool inplace)
 {
+   bool        result = true;
    Oid         reloid;
    Relation    crel;
-   int32       relpages = DEFAULT_RELPAGES;
+   BlockNumber relpages = 0;
    bool        update_relpages = false;
-   float       reltuples = DEFAULT_RELTUPLES;
+   float       reltuples = 0;
    bool        update_reltuples = false;
-   int32       relallvisible = DEFAULT_RELALLVISIBLE;
+   BlockNumber relallvisible = 0;
    bool        update_relallvisible = false;
-   bool        result = true;
 
    if (!PG_ARGISNULL(RELPAGES_ARG))
    {
-       relpages = PG_GETARG_INT32(RELPAGES_ARG);
-
-       /*
-        * Partitioned tables may have relpages=-1. Note: for relations with
-        * no storage, relpages=-1 is not used consistently, but must be
-        * supported here.
-        */
-       if (relpages < -1)
-       {
-           ereport(elevel,
-                   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-                    errmsg("relpages cannot be < -1")));
-           result = false;
-       }
-       else
-           update_relpages = true;
+       relpages = PG_GETARG_UINT32(RELPAGES_ARG);
+       update_relpages = true;
    }
 
    if (!PG_ARGISNULL(RELTUPLES_ARG))
    {
        reltuples = PG_GETARG_FLOAT4(RELTUPLES_ARG);
-
        if (reltuples < -1.0)
        {
            ereport(elevel,
@@ -107,17 +89,8 @@ relation_statistics_update(FunctionCallInfo fcinfo, int elevel, bool inplace)
 
    if (!PG_ARGISNULL(RELALLVISIBLE_ARG))
    {
-       relallvisible = PG_GETARG_INT32(RELALLVISIBLE_ARG);
-
-       if (relallvisible < 0)
-       {
-           ereport(elevel,
-                   (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-                    errmsg("relallvisible cannot be < 0")));
-           result = false;
-       }
-       else
-           update_relallvisible = true;
+       relallvisible = PG_GETARG_UINT32(RELALLVISIBLE_ARG);
+       update_relallvisible = true;
    }
 
    stats_check_required_arg(fcinfo, relarginfo, RELATION_ARG);
@@ -201,7 +174,7 @@ relation_statistics_update(FunctionCallInfo fcinfo, int elevel, bool inplace)
        if (update_relpages && relpages != pgcform->relpages)
        {
            replaces[nreplaces] = Anum_pg_class_relpages;
-           values[nreplaces] = Int32GetDatum(relpages);
+           values[nreplaces] = UInt32GetDatum(relpages);
            nreplaces++;
        }
 
@@ -215,7 +188,7 @@ relation_statistics_update(FunctionCallInfo fcinfo, int elevel, bool inplace)
        if (update_relallvisible && relallvisible != pgcform->relallvisible)
        {
            replaces[nreplaces] = Anum_pg_class_relallvisible;
-           values[nreplaces] = Int32GetDatum(relallvisible);
+           values[nreplaces] = UInt32GetDatum(relallvisible);
            nreplaces++;
        }
 
@@ -263,11 +236,11 @@ pg_clear_relation_stats(PG_FUNCTION_ARGS)
 
    newfcinfo->args[0].value = PG_GETARG_OID(0);
    newfcinfo->args[0].isnull = PG_ARGISNULL(0);
-   newfcinfo->args[1].value = DEFAULT_RELPAGES;
+   newfcinfo->args[1].value = UInt32GetDatum(0);
    newfcinfo->args[1].isnull = false;
-   newfcinfo->args[2].value = DEFAULT_RELTUPLES;
+   newfcinfo->args[2].value = Float4GetDatum(-1.0);
    newfcinfo->args[2].isnull = false;
-   newfcinfo->args[3].value = DEFAULT_RELALLVISIBLE;
+   newfcinfo->args[3].value = UInt32GetDatum(0);
    newfcinfo->args[3].isnull = false;
 
    relation_statistics_update(newfcinfo, ERROR, false);