Replace SearchSysCacheGetAttribute with SysCacheGetAttr, which fetches
authorTom Lane
Sun, 23 Jan 2000 03:43:24 +0000 (03:43 +0000)
committerTom Lane
Sun, 23 Jan 2000 03:43:24 +0000 (03:43 +0000)
an attribute of a tuple previously fetched with SearchSysCacheTuple.
This avoids a lot of redundant cache lookups, particularly in selfuncs.c.
Also, remove SearchSysCacheStruct, which was unused and grotty.

src/backend/utils/adt/selfuncs.c
src/backend/utils/cache/fcache.c
src/backend/utils/cache/lsyscache.c
src/backend/utils/cache/syscache.c
src/include/utils/syscache.h

index 6af241f9a182c7e63c55f195aaaa81f737144426..5838fdc471ff2fa07bebb5bd6ccec56a8891dfa3 100644 (file)
@@ -14,7 +14,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.50 2000/01/23 02:06:56 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.51 2000/01/23 03:43:23 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -587,9 +587,6 @@ getattproperties(Oid relid, AttrNumber attnum,
  * commonval, loval, hival are returned as Datums holding the internal
  * representation of the values.  (Note that these should be pfree'd
  * after use if the data type is not by-value.)
- *
- * XXX currently, this does a linear search of pg_statistic because there
- * is no index nor syscache for pg_statistic.  FIX THIS!
  */
 static bool
 getattstatistics(Oid relid, AttrNumber attnum, Oid opid, Oid typid,
@@ -600,29 +597,26 @@ getattstatistics(Oid relid, AttrNumber attnum, Oid opid, Oid typid,
                 Datum *loval,
                 Datum *hival)
 {
-   Relation    rel;
-   bool        isnull;
    HeapTuple   tuple;
    HeapTuple   typeTuple;
    FmgrInfo    inputproc;
    Oid         typelem;
+   bool        isnull;
 
-   rel = heap_openr(StatisticRelationName, AccessShareLock);
-
+   /* We assume that there will only be one entry in pg_statistic
+    * for the given rel/att.  Someday, VACUUM might store more than one...
+    */
    tuple = SearchSysCacheTuple(STATRELID,
-                                   ObjectIdGetDatum(relid),
-                                   Int16GetDatum((int16) attnum),
-                                   opid, 0);
+                               ObjectIdGetDatum(relid),
+                               Int16GetDatum((int16) attnum),
+                               opid,
+                               0);
    if (!HeapTupleIsValid(tuple))
    {
        /* no such stats entry */
-       heap_close(rel, AccessShareLock);
        return false;
    }
 
-   /* We assume that there will only be one entry in pg_statistic
-    * for the given rel/att.  Someday, VACUUM might store more than one...
-    */
    if (nullfrac)
        *nullfrac = ((Form_pg_statistic) GETSTRUCT(tuple))->stanullfrac;
    if (commonfrac)
@@ -639,14 +633,13 @@ getattstatistics(Oid relid, AttrNumber attnum, Oid opid, Oid typid,
    typelem = ((Form_pg_type) GETSTRUCT(typeTuple))->typelem;
 
    /* Values are variable-length fields, so cannot access as struct fields.
-    * Must do it the hard way with heap_getattr.
+    * Must do it the hard way with SysCacheGetAttr.
     */
    if (commonval)
    {
-       text *val = (text *) heap_getattr(tuple,
-                                         Anum_pg_statistic_stacommonval,
-                                         RelationGetDescr(rel),
-                                         &isnull);
+       text *val = (text *) SysCacheGetAttr(STATRELID, tuple,
+                                            Anum_pg_statistic_stacommonval,
+                                            &isnull);
        if (isnull)
        {
            elog(DEBUG, "getattstatistics: stacommonval is null");
@@ -663,10 +656,9 @@ getattstatistics(Oid relid, AttrNumber attnum, Oid opid, Oid typid,
 
    if (loval)
    {
-       text *val = (text *) heap_getattr(tuple,
-                                         Anum_pg_statistic_staloval,
-                                         RelationGetDescr(rel),
-                                         &isnull);
+       text *val = (text *) SysCacheGetAttr(STATRELID, tuple,
+                                            Anum_pg_statistic_staloval,
+                                            &isnull);
        if (isnull)
        {
            elog(DEBUG, "getattstatistics: staloval is null");
@@ -683,10 +675,9 @@ getattstatistics(Oid relid, AttrNumber attnum, Oid opid, Oid typid,
 
    if (hival)
    {
-       text *val = (text *) heap_getattr(tuple,
-                                         Anum_pg_statistic_stahival,
-                                         RelationGetDescr(rel),
-                                         &isnull);
+       text *val = (text *) SysCacheGetAttr(STATRELID, tuple,
+                                            Anum_pg_statistic_stahival,
+                                            &isnull);
        if (isnull)
        {
            elog(DEBUG, "getattstatistics: stahival is null");
@@ -701,7 +692,6 @@ getattstatistics(Oid relid, AttrNumber attnum, Oid opid, Oid typid,
        }
    }
 
-   heap_close(rel, AccessShareLock);
    return true;
 }
 
index 69ef78af096c51f78933316dc625800b7676a2a5..49a2642e8676406c0c1ba1bb552aacbc875c786a 100644 (file)
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/utils/cache/Attic/fcache.c,v 1.27 1999/11/22 17:56:32 momjian Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/utils/cache/Attic/fcache.c,v 1.28 2000/01/23 03:43:24 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -74,13 +74,12 @@ init_fcache(Oid foid,
    Form_pg_proc procedureStruct;
    Form_pg_type typeStruct;
    FunctionCachePtr retval;
-   text       *tmp;
    int         nargs;
+   text       *tmp;
+   bool        isNull;
 
    /* ----------------
-    *   get the procedure tuple corresponding to the given
-    *   functionOid.  If this fails, returnValue has been
-    *   pre-initialized to "null" so we just return it.
+    *   get the procedure tuple corresponding to the given functionOid
     * ----------------
     */
    retval = (FunctionCachePtr) palloc(sizeof(FunctionCache));
@@ -94,20 +93,13 @@ init_fcache(Oid foid,
                                         0, 0, 0);
 
    if (!HeapTupleIsValid(procedureTuple))
-       elog(ERROR,
-            "init_fcache: %s %u",
-            "Cache lookup failed for procedure", foid);
+       elog(ERROR, "init_fcache: Cache lookup failed for procedure %u",
+            foid);
 
-   /* ----------------
-    *   get the return type from the procedure tuple
-    * ----------------
-    */
    procedureStruct = (Form_pg_proc) GETSTRUCT(procedureTuple);
 
    /* ----------------
-    *   get the type tuple corresponding to the return type
-    *   If this fails, returnValue has been pre-initialized
-    *   to "null" so we just return it.
+    *   get the return type from the procedure tuple
     * ----------------
     */
    typeTuple = SearchSysCacheTuple(TYPEOID,
@@ -115,27 +107,24 @@ init_fcache(Oid foid,
                                    0, 0, 0);
 
    if (!HeapTupleIsValid(typeTuple))
-       elog(ERROR,
-            "init_fcache: %s %u",
-            "Cache lookup failed for type",
-            (procedureStruct)->prorettype);
+       elog(ERROR, "init_fcache: Cache lookup failed for type %u",
+            procedureStruct->prorettype);
+
+   typeStruct = (Form_pg_type) GETSTRUCT(typeTuple);
 
    /* ----------------
     *   get the type length and by-value from the type tuple and
     *   save the information in our one element cache.
     * ----------------
     */
-   typeStruct = (Form_pg_type) GETSTRUCT(typeTuple);
-
-   retval->typlen = (typeStruct)->typlen;
-   if ((typeStruct)->typrelid == InvalidOid)
+   retval->typlen = typeStruct->typlen;
+   if (typeStruct->typrelid == InvalidOid)
    {
        /* The return type is not a relation, so just use byval */
-       retval->typbyval = (typeStruct)->typbyval ? true : false;
+       retval->typbyval = typeStruct->typbyval;
    }
    else
    {
-
        /*
         * This is a hack.  We assume here that any function returning a
         * relation returns it by reference.  This needs to be fixed.
@@ -147,7 +136,7 @@ init_fcache(Oid foid,
    retval->func_state = (char *) NULL;
    retval->setArg = NULL;
    retval->hasSetArg = false;
-   retval->oneResult = !procedureStruct->proretset;
+   retval->oneResult = ! procedureStruct->proretset;
    retval->istrusted = procedureStruct->proistrusted;
 
    /*
@@ -157,8 +146,8 @@ init_fcache(Oid foid,
     * allocated by the executor (i.e. slots and tuples) is freed.
     */
    if ((retval->language == SQLlanguageId) &&
-       (retval->oneResult) &&
-       !(retval->typbyval))
+       retval->oneResult &&
+       ! retval->typbyval)
    {
        Form_pg_class relationStruct;
        HeapTuple   relationTuple;
@@ -198,7 +187,7 @@ init_fcache(Oid foid,
    {
        Oid        *argTypes;
 
-       retval->nullVect = (bool *) palloc((retval->nargs) * sizeof(bool));
+       retval->nullVect = (bool *) palloc(retval->nargs * sizeof(bool));
 
        if (retval->language == SQLlanguageId)
        {
@@ -230,43 +219,36 @@ init_fcache(Oid foid,
        retval->nullVect = (BoolPtr) NULL;
    }
 
-   /*
-    * XXX this is the first varlena in the struct.  If the order changes
-    * for some reason this will fail.
-    */
    if (procedureStruct->prolang == SQLlanguageId)
    {
-       retval->src = textout(&(procedureStruct->prosrc));
+       tmp = (text *) SysCacheGetAttr(PROCOID,
+                                      procedureTuple,
+                                      Anum_pg_proc_prosrc,
+                                      &isNull);
+       if (isNull)
+           elog(ERROR, "init_fcache: null prosrc for procedure %u",
+                foid);
+       retval->src = textout(tmp);
        retval->bin = (char *) NULL;
    }
    else
    {
-
-       /*
-        * I'm not sure that we even need to do this at all.
-        */
-
-       /*
-        * We do for untrusted functions.
-        */
-
+       retval->src = (char *) NULL;
        if (procedureStruct->proistrusted)
            retval->bin = (char *) NULL;
        else
        {
-           tmp = (text *)
-               SearchSysCacheGetAttribute(PROCOID,
+           tmp = (text *) SysCacheGetAttr(PROCOID,
+                                          procedureTuple,
                                           Anum_pg_proc_probin,
-                                          ObjectIdGetDatum(foid),
-                                          0, 0, 0);
+                                          &isNull);
+           if (isNull)
+               elog(ERROR, "init_fcache: null probin for procedure %u",
+                    foid);
            retval->bin = textout(tmp);
        }
-       retval->src = (char *) NULL;
    }
 
-
-
-
    if (retval->language != SQLlanguageId)
    {
        fmgr_info(foid, &(retval->func));
@@ -275,7 +257,6 @@ init_fcache(Oid foid,
    else
        retval->func.fn_addr = (func_ptr) NULL;
 
-
    return retval;
 }
 
index 1c34486b7497d62042b79c7919187d50289f51c3..406c476182be476d7245ad3e5b1834e92c007daa 100644 (file)
@@ -6,7 +6,7 @@
  * Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.37 1999/12/31 03:18:43 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.38 2000/01/23 03:43:24 tgl Exp $
  *
  * NOTES
  *   Eventually, the index information should go through here, too.
@@ -617,35 +617,15 @@ get_typalign(Oid typid)
 Datum
 get_typdefault(Oid typid)
 {
-   struct varlena *typDefault;
-   int32       dataSize;
    HeapTuple   typeTuple;
    Form_pg_type type;
+   struct varlena *typDefault;
+   bool        isNull;
+   int32       dataSize;
    int32       typLen;
    bool        typByVal;
    Datum       returnValue;
 
-   /*
-    * First, see if there is a non-null typdefault field (usually there isn't)
-    */
-   typDefault = (struct varlena *)
-       SearchSysCacheGetAttribute(TYPEOID,
-                                  Anum_pg_type_typdefault,
-                                  ObjectIdGetDatum(typid),
-                                  0, 0, 0);
-
-   if (typDefault == NULL)
-       return PointerGetDatum(NULL);
-
-   dataSize = VARSIZE(typDefault) - VARHDRSZ;
-
-   /*
-    * Need the type's length and byVal fields.
-    *
-    * XXX silly to repeat the syscache search that SearchSysCacheGetAttribute
-    * just did --- but at present this path isn't taken often enough to
-    * make it worth fixing.
-    */
    typeTuple = SearchSysCacheTuple(TYPEOID,
                                    ObjectIdGetDatum(typid),
                                    0, 0, 0);
@@ -654,6 +634,22 @@ get_typdefault(Oid typid)
        elog(ERROR, "get_typdefault: failed to lookup type %u", typid);
 
    type = (Form_pg_type) GETSTRUCT(typeTuple);
+
+   /*
+    * First, see if there is a non-null typdefault field (usually there isn't)
+    */
+   typDefault = (struct varlena *) SysCacheGetAttr(TYPEOID,
+                                                   typeTuple,
+                                                   Anum_pg_type_typdefault,
+                                                   &isNull);
+
+   if (isNull)
+       return PointerGetDatum(NULL);
+
+   /*
+    * Otherwise, extract/copy the value.
+    */
+   dataSize = VARSIZE(typDefault) - VARHDRSZ;
    typLen = type->typlen;
    typByVal = type->typbyval;
 
index 9c94c1e05a14380ca35d56f6d11746af8ba80eb8..0d4c1e3e056855cc81003c3812642834453add50 100644 (file)
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/utils/cache/syscache.c,v 1.44 1999/11/24 17:09:27 momjian Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/utils/cache/syscache.c,v 1.45 2000/01/23 03:43:24 tgl Exp $
  *
  * NOTES
  *   These routines allow the parser/planner/executor to perform
@@ -535,140 +535,42 @@ SearchSysCacheTuple(int cacheId,/* cache selection code */
    return tp;
 }
 
-/*
- * SearchSysCacheStruct
- *   Fills 's' with the information retrieved by calling SearchSysCache()
- *   with arguments key1...key4.  Retrieves only the portion of the tuple
- *   which is not variable-length.
- *
- * NOTE: we are assuming that non-variable-length fields in the system
- *      catalogs will always be defined!
- *
- * Returns 1L if a tuple was found, 0L if not.
- */
-int32
-SearchSysCacheStruct(int cacheId,      /* cache selection code */
-                    char *returnStruct,        /* (preallocated!) */
-                    Datum key1,
-                    Datum key2,
-                    Datum key3,
-                    Datum key4)
-{
-   HeapTuple   tp;
-
-   if (!PointerIsValid(returnStruct))
-   {
-       elog(ERROR, "SearchSysCacheStruct: No receiving struct");
-       return 0;
-   }
-   tp = SearchSysCacheTuple(cacheId, key1, key2, key3, key4);
-   if (!HeapTupleIsValid(tp))
-       return 0;
-   memcpy(returnStruct, (char *) GETSTRUCT(tp), cacheinfo[cacheId].size);
-   return 1;
-}
-
 
 /*
- * SearchSysCacheGetAttribute
- *   Returns the attribute corresponding to 'attributeNumber' for
- *   a given cached tuple.  This routine usually needs to be used for
- *   attributes that might be NULL or might be at a variable offset
- *   in the tuple.
+ * SysCacheGetAttr
+ *
+ *     Given a tuple previously fetched by SearchSysCacheTuple() or
+ *     SearchSysCacheTupleCopy(), extract a specific attribute.
  *
- * XXX This re-opens the relation, so this is slower than just pulling
- * fixed-location fields out of the struct returned by SearchSysCacheTuple.
+ * This is equivalent to using heap_getattr() on a tuple fetched
+ * from a non-cached relation.  Usually, this is only used for attributes
+ * that could be NULL or variable length; the fixed-size attributes in
+ * a system table are accessed just by mapping the tuple onto the C struct
+ * declarations from include/catalog/.
  *
- * [callers all assume this returns a (struct varlena *). -ay 10/94]
+ * As with heap_getattr(), if the attribute is of a pass-by-reference type
+ * then a pointer into the tuple data area is returned --- the caller must
+ * not modify or pfree the datum!
  */
-void *
-SearchSysCacheGetAttribute(int cacheId,
-                          AttrNumber attributeNumber,
-                          Datum key1,
-                          Datum key2,
-                          Datum key3,
-                          Datum key4)
+Datum
+SysCacheGetAttr(int cacheId, HeapTuple tup,
+               AttrNumber attributeNumber,
+               bool *isnull)
 {
-   HeapTuple   tp;
-   char       *cacheName;
-   Relation    relation;
-   int32       attributeLength,
-               attributeByValue;
-   bool        isNull;
-   Datum       attributeValue;
-   void       *returnValue;
-
    /*
-    * Open the relation first, to ensure we are in sync with SI inval
-    * events --- we don't want the tuple found in the cache to be
-    * invalidated out from under us.
+    * We just need to get the TupleDesc out of the cache entry,
+    * and then we can apply heap_getattr().  We expect that the cache
+    * control data is currently valid --- if the caller just fetched
+    * the tuple, then it should be.
     */
-   cacheName = cacheinfo[cacheId].name;
-   relation = heap_openr(cacheName, AccessShareLock);
-
-   tp = SearchSysCacheTuple(cacheId, key1, key2, key3, key4);
-
-   if (!HeapTupleIsValid(tp))
-   {
-       heap_close(relation, AccessShareLock);
-#ifdef CACHEDEBUG
-       elog(DEBUG,
-            "SearchSysCacheGetAttribute: Lookup in %s(%d) failed",
-            cacheName, cacheId);
-#endif  /* defined(CACHEDEBUG) */
-       return NULL;
-   }
-
-   if (attributeNumber < 0 &&
-       attributeNumber > FirstLowInvalidHeapAttributeNumber)
-   {
-       attributeLength = heap_sysattrlen(attributeNumber);
-       attributeByValue = heap_sysattrbyval(attributeNumber);
-   }
-   else if (attributeNumber > 0 &&
-            attributeNumber <= relation->rd_rel->relnatts)
-   {
-       attributeLength = relation->rd_att->attrs[attributeNumber - 1]->attlen;
-       attributeByValue = relation->rd_att->attrs[attributeNumber - 1]->attbyval;
-   }
-   else
-   {
-       heap_close(relation, AccessShareLock);
-       elog(ERROR,
-            "SearchSysCacheGetAttribute: Bad attr # %d in %s(%d)",
-            attributeNumber, cacheName, cacheId);
-       return NULL;
-   }
-
-   attributeValue = heap_getattr(tp,
-                                 attributeNumber,
-                                 RelationGetDescr(relation),
-                                 &isNull);
-
-   if (isNull)
-   {
-       /*
-        * Used to be an elog(DEBUG, ...) here and a claim that it should
-        * be a FATAL error, I don't think either is warranted -mer 6/9/92
-        */
-       heap_close(relation, AccessShareLock);
-       return NULL;
-   }
-
-   if (attributeByValue)
-       returnValue = (void *) attributeValue;
-   else
-   {
-       char       *tmp;
-       int         size = (attributeLength < 0)
-       ? VARSIZE((struct varlena *) attributeValue)    /* variable length */
-       : attributeLength;      /* fixed length */
-
-       tmp = (char *) palloc(size);
-       memcpy(tmp, (void *) attributeValue, size);
-       returnValue = (void *) tmp;
-   }
-
-   heap_close(relation, AccessShareLock);
-   return returnValue;
+   if (cacheId < 0 || cacheId >= SysCacheSize)
+       elog(ERROR, "SysCacheGetAttr: Bad cache id %d", cacheId);
+   if (! PointerIsValid(SysCache[cacheId]) ||
+       SysCache[cacheId]->relationId == InvalidOid ||
+       ! PointerIsValid(SysCache[cacheId]->cc_tupdesc))
+       elog(ERROR, "SysCacheGetAttr: missing cache data for id %d", cacheId);
+
+   return heap_getattr(tup, attributeNumber,
+                       SysCache[cacheId]->cc_tupdesc,
+                       isnull);
 }
index 158a7bdb367ae60d86281c61943629bb3365cb97..a6acff02654419a60a6ec05cd83ffee25819f703 100644 (file)
@@ -8,7 +8,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: syscache.h,v 1.22 1999/11/24 16:52:50 momjian Exp $
+ * $Id: syscache.h,v 1.23 2000/01/23 03:43:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -81,10 +81,8 @@ extern HeapTuple SearchSysCacheTupleCopy(int cacheId,
                        Datum key1, Datum key2, Datum key3, Datum key4);
 extern HeapTuple SearchSysCacheTuple(int cacheId,
                    Datum key1, Datum key2, Datum key3, Datum key4);
-extern int32 SearchSysCacheStruct(int cacheId, char *returnStruct,
-                    Datum key1, Datum key2, Datum key3, Datum key4);
-extern void *SearchSysCacheGetAttribute(int cacheId,
-                          AttrNumber attributeNumber,
-                        Datum key1, Datum key2, Datum key3, Datum key4);
+extern Datum SysCacheGetAttr(int cacheId, HeapTuple tup,
+                            AttrNumber attributeNumber,
+                            bool *isnull);
 
 #endif  /* SYSCACHE_H */