void
PLy_output_tuple_funcs(PLyTypeInfo *arg, TupleDesc desc)
{
	int			i;

	if (arg->is_rowtype == 0)
		elog(ERROR, "PLyTypeInfo struct is initialized for a Datum");
	arg->is_rowtype = 1;

	if (arg->out.r.natts != desc->natts)
	{
		if (arg->out.r.atts)
			PLy_free(arg->out.r.atts);
		arg->out.r.natts = desc->natts;
		arg->out.r.atts = PLy_malloc0(desc->natts * sizeof(PLyDatumToOb));
	}

	Assert(OidIsValid(desc->tdtypeid));

	/*
	 * RECORDOID means we got called to create output functions for an
	 * anonymous record type
	 */
	if (desc->tdtypeid != RECORDOID)
	{
		HeapTuple	relTup;

		/* Get the pg_class tuple corresponding to the type of the output */
		arg->typ_relid = typeidTypeRelid(desc->tdtypeid);
		relTup = SearchSysCache1(RELOID, ObjectIdGetDatum(arg->typ_relid));
		if (!HeapTupleIsValid(relTup))
			elog(ERROR, "cache lookup failed for relation %u", arg->typ_relid);

		/* Remember XMIN and TID for later validation if cache is still OK */
		arg->typrel_xmin = HeapTupleHeaderGetXmin(relTup->t_data);
		arg->typrel_tid = relTup->t_self;

		ReleaseSysCache(relTup);
	}

	for (i = 0; i < desc->natts; i++)
	{
		HeapTuple	typeTup;

		if (desc->attrs[i]->attisdropped)
			continue;

		if (arg->out.r.atts[i].typoid == desc->attrs[i]->atttypid)
			continue;			/* already set up this entry */

		typeTup = SearchSysCache1(TYPEOID,
								  ObjectIdGetDatum(desc->attrs[i]->atttypid));
		if (!HeapTupleIsValid(typeTup))
			elog(ERROR, "cache lookup failed for type %u",
				 desc->attrs[i]->atttypid);

		PLy_output_datum_func2(&(arg->out.r.atts[i]), typeTup);

		ReleaseSysCache(typeTup);
	}
}

//.........这里部分代码省略.........
									TypeNameToString(t))));
			}
			toid = typeTypeId(typtup);
			ReleaseSysCache(typtup);
		}
		else
		{
			ereport(ERROR,
					(errcode(ERRCODE_UNDEFINED_OBJECT),
					 errmsg("type %s does not exist",
							TypeNameToString(t))));
			toid = InvalidOid;	/* keep compiler quiet */
		}

		aclresult = pg_type_aclcheck(toid, GetUserId(), ACL_USAGE);
		if (aclresult != ACLCHECK_OK)
			aclcheck_error_type(aclresult, toid);

		if (t->setof)
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
					 errmsg("functions cannot accept set arguments")));

		/* handle input parameters */
		if (fp->mode != FUNC_PARAM_OUT && fp->mode != FUNC_PARAM_TABLE)
		{
			/* other input parameters can't follow a VARIADIC parameter */
			if (varCount > 0)
				ereport(ERROR,
						(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
						 errmsg("VARIADIC parameter must be the last input parameter")));
			inTypes[inCount++] = toid;
			isinput = true;
		}

		/* handle output parameters */
		if (fp->mode != FUNC_PARAM_IN && fp->mode != FUNC_PARAM_VARIADIC)
		{
			if (outCount == 0)	/* save first output param's type */
				*requiredResultType = toid;
			outCount++;
		}

		if (fp->mode == FUNC_PARAM_VARIADIC)
		{
			varCount++;
			/* validate variadic parameter type */
			switch (toid)
			{
				case ANYARRAYOID:
				case ANYOID:
					/* okay */
					break;
				default:
					if (!OidIsValid(get_element_type(toid)))
						ereport(ERROR,
								(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
							 errmsg("VARIADIC parameter must be an array")));
					break;
			}
		}

		allTypes[i] = ObjectIdGetDatum(toid);

		paramModes[i] = CharGetDatum(fp->mode);

		if (fp->name && fp->name[0])
		{
			ListCell   *px;

			/*
			 * As of Postgres 9.0 we disallow using the same name for two
			 * input or two output function parameters.  Depending on the
			 * function's language, conflicting input and output names might
			 * be bad too, but we leave it to the PL to complain if so.
			 */
			foreach(px, parameters)
			{
				FunctionParameter *prevfp = (FunctionParameter *) lfirst(px);

				if (prevfp == fp)
					break;
				/* pure in doesn't conflict with pure out */
				if ((fp->mode == FUNC_PARAM_IN ||
					 fp->mode == FUNC_PARAM_VARIADIC) &&
					(prevfp->mode == FUNC_PARAM_OUT ||
					 prevfp->mode == FUNC_PARAM_TABLE))
					continue;
				if ((prevfp->mode == FUNC_PARAM_IN ||
					 prevfp->mode == FUNC_PARAM_VARIADIC) &&
					(fp->mode == FUNC_PARAM_OUT ||
					 fp->mode == FUNC_PARAM_TABLE))
					continue;
				if (prevfp->name && prevfp->name[0] &&
					strcmp(prevfp->name, fp->name) == 0)
					ereport(ERROR,
							(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
						  errmsg("parameter name \"%s\" used more than once",
								 fp->name)));
			}

//.........这里部分代码省略.........
			switch (allParams[i])
			{
				case ANYARRAYOID:
				case ANYELEMENTOID:
				case ANYNONARRAYOID:
				case ANYENUMOID:
					genericOutParam = true;
					break;
				case INTERNALOID:
					internalOutParam = true;
					break;
			}
		}
	}

	if ((IsPolymorphicType(returnType) || genericOutParam)
		&& !genericInParam)
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
				 errmsg("cannot determine result data type"),
				 errdetail("A function returning a polymorphic type must have at least one polymorphic argument.")));

	if ((returnType == INTERNALOID || internalOutParam) && !internalInParam)
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
				 errmsg("unsafe use of pseudo-type \"internal\""),
				 errdetail("A function returning \"internal\" must have at least one \"internal\" argument.")));

	/*
	 * don't allow functions of complex types that have the same name as
	 * existing attributes of the type
	 */
	if (parameterCount == 1 &&
		OidIsValid(parameterTypes->values[0]) &&
		(relid = typeidTypeRelid(parameterTypes->values[0])) != InvalidOid &&
		get_attnum(relid, procedureName) != InvalidAttrNumber)
		ereport(ERROR,
				(errcode(ERRCODE_DUPLICATE_COLUMN),
				 errmsg("\"%s\" is already an attribute of type %s",
						procedureName,
						format_type_be(parameterTypes->values[0]))));

	if (parameterModes != PointerGetDatum(NULL))
	{
		/*
		 * We expect the array to be a 1-D CHAR array; verify that. We don't
		 * need to use deconstruct_array() since the array data is just going
		 * to look like a C array of char values.
		 */
		ArrayType  *modesArray = (ArrayType *) DatumGetPointer(parameterModes);
		char	   *modes;

		if (ARR_NDIM(modesArray) != 1 ||
			ARR_DIMS(modesArray)[0] != allParamCount ||
			ARR_HASNULL(modesArray) ||
			ARR_ELEMTYPE(modesArray) != CHAROID)
			elog(ERROR, "parameterModes is not a 1-D char array");
		modes = (char *) ARR_DATA_PTR(modesArray);

		/*
		 * Only the last input parameter can be variadic; if it is, save its
		 * element type.  Errors here are just elog since caller should have
		 * checked this already.
		 */
		for (i = 0; i < allParamCount; i++)
		{

/*
 * GenerateTypeDependencies: build the dependencies needed for a type
 *
 * If rebuild is true, we remove existing dependencies and rebuild them
 * from scratch.  This is needed for ALTER TYPE, and also when replacing
 * a shell type.  We don't remove an existing extension dependency, though.
 * (That means an extension can't absorb a shell type created in another
 * extension, nor ALTER a type created by another extension.  Also, if it
 * replaces a free-standing shell type or ALTERs a free-standing type,
 * that type will become a member of the extension.)
 */
void
GenerateTypeDependencies(Oid typeNamespace,
						 Oid typeObjectId,
						 Oid relationOid,		/* only for relation rowtypes */
						 char relationKind,		/* ditto */
						 Oid owner,
						 Oid inputProcedure,
						 Oid outputProcedure,
						 Oid receiveProcedure,
						 Oid sendProcedure,
						 Oid typmodinProcedure,
						 Oid typmodoutProcedure,
						 Oid analyzeProcedure,
						 Oid elementType,
						 bool isImplicitArray,
						 Oid baseType,
						 Oid typeCollation,
						 Node *defaultExpr,
						 bool rebuild)
{
	ObjectAddress myself,
				referenced;

	/* If rebuild, first flush old dependencies, except extension deps */
	if (rebuild)
	{
		deleteDependencyRecordsFor(TypeRelationId, typeObjectId, true);
		deleteSharedDependencyRecordsFor(TypeRelationId, typeObjectId, 0);
	}

	myself.classId = TypeRelationId;
	myself.objectId = typeObjectId;
	myself.objectSubId = 0;

	/*
	 * Make dependencies on namespace, owner, extension.
	 *
	 * For a relation rowtype (that's not a composite type), we should skip
	 * these because we'll depend on them indirectly through the pg_class
	 * entry.  Likewise, skip for implicit arrays since we'll depend on them
	 * through the element type.
	 */
	if ((!OidIsValid(relationOid) || relationKind == RELKIND_COMPOSITE_TYPE) &&
		!isImplicitArray)
	{
		referenced.classId = NamespaceRelationId;
		referenced.objectId = typeNamespace;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);

		recordDependencyOnOwner(TypeRelationId, typeObjectId, owner);

		recordDependencyOnCurrentExtension(&myself, rebuild);
	}

	/* Normal dependencies on the I/O functions */
	if (OidIsValid(inputProcedure))
	{
		referenced.classId = ProcedureRelationId;
		referenced.objectId = inputProcedure;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
	}

	if (OidIsValid(outputProcedure))
	{
		referenced.classId = ProcedureRelationId;
		referenced.objectId = outputProcedure;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
	}

	if (OidIsValid(receiveProcedure))
	{
		referenced.classId = ProcedureRelationId;
		referenced.objectId = receiveProcedure;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
	}

	if (OidIsValid(sendProcedure))
	{
		referenced.classId = ProcedureRelationId;
		referenced.objectId = sendProcedure;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
	}

	if (OidIsValid(typmodinProcedure))
//.........这里部分代码省略.........

//.........这里部分代码省略.........

	/* minmax_aggs list should be empty at this point */
	Assert(root->minmax_aggs == NIL);

	/* Nothing to do if query has no aggregates */
	if (!parse->hasAggs)
		return;

	Assert(!parse->setOperations);		/* shouldn't get here if a setop */
	Assert(parse->rowMarks == NIL);		/* nor if FOR UPDATE */

	/*
	 * Reject unoptimizable cases.
	 *
	 * We don't handle GROUP BY or windowing, because our current
	 * implementations of grouping require looking at all the rows anyway, and
	 * so there's not much point in optimizing MIN/MAX.  (Note: relaxing this
	 * would likely require some restructuring in grouping_planner(), since it
	 * performs assorted processing related to these features between calling
	 * preprocess_minmax_aggregates and optimize_minmax_aggregates.)
	 */
	if (parse->groupClause || parse->hasWindowFuncs)
		return;

	/*
	 * We also restrict the query to reference exactly one table, since join
	 * conditions can't be handled reasonably.  (We could perhaps handle a
	 * query containing cartesian-product joins, but it hardly seems worth the
	 * trouble.)  However, the single table could be buried in several levels
	 * of FromExpr due to subqueries.  Note the "single" table could be an
	 * inheritance parent, too, including the case of a UNION ALL subquery
	 * that's been flattened to an appendrel.
	 */
	jtnode = parse->jointree;
	while (IsA(jtnode, FromExpr))
	{
		if (list_length(jtnode->fromlist) != 1)
			return;
		jtnode = linitial(jtnode->fromlist);
	}
	if (!IsA(jtnode, RangeTblRef))
		return;
	rtr = (RangeTblRef *) jtnode;
	rte = planner_rt_fetch(rtr->rtindex, root);
	if (rte->rtekind == RTE_RELATION)
		 /* ordinary relation, ok */ ;
	else if (rte->rtekind == RTE_SUBQUERY && rte->inh)
		 /* flattened UNION ALL subquery, ok */ ;
	else
		return;

	/*
	 * Scan the tlist and HAVING qual to find all the aggregates and verify
	 * all are MIN/MAX aggregates.	Stop as soon as we find one that isn't.
	 */
	aggs_list = NIL;
	if (find_minmax_aggs_walker((Node *) tlist, &aggs_list))
		return;
	if (find_minmax_aggs_walker(parse->havingQual, &aggs_list))
		return;

	/*
	 * OK, there is at least the possibility of performing the optimization.
	 * Build an access path for each aggregate.  (We must do this now because
	 * we need to call query_planner with a pristine copy of the current query
	 * tree; it'll be too late when optimize_minmax_aggregates gets called.)
	 * If any of the aggregates prove to be non-indexable, give up; there is
	 * no point in optimizing just some of them.
	 */
	foreach(lc, aggs_list)
	{
		MinMaxAggInfo *mminfo = (MinMaxAggInfo *) lfirst(lc);
		Oid			eqop;
		bool		reverse;

		/*
		 * We'll need the equality operator that goes with the aggregate's
		 * ordering operator.
		 */
		eqop = get_equality_op_for_ordering_op(mminfo->aggsortop, &reverse);
		if (!OidIsValid(eqop))	/* shouldn't happen */
			elog(ERROR, "could not find equality operator for ordering operator %u",
				 mminfo->aggsortop);

		/*
		 * We can use either an ordering that gives NULLS FIRST or one that
		 * gives NULLS LAST; furthermore there's unlikely to be much
		 * performance difference between them, so it doesn't seem worth
		 * costing out both ways if we get a hit on the first one.	NULLS
		 * FIRST is more likely to be available if the operator is a
		 * reverse-sort operator, so try that first if reverse.
		 */
		if (build_minmax_path(root, mminfo, eqop, mminfo->aggsortop, reverse))
			continue;
		if (build_minmax_path(root, mminfo, eqop, mminfo->aggsortop, !reverse))
			continue;

		/* No indexable path for this aggregate, so fail */
		return;
	}

/*
 * Common subroutine for num_nulls() and num_nonnulls().
 * Returns TRUE if successful, FALSE if function should return NULL.
 * If successful, total argument count and number of nulls are
 * returned into *nargs and *nulls.
 */
static bool
count_nulls(FunctionCallInfo fcinfo,
			int32 *nargs, int32 *nulls)
{
	int32		count = 0;
	int			i;

	/* Did we get a VARIADIC array argument, or separate arguments? */
	if (get_fn_expr_variadic(fcinfo->flinfo))
	{
		ArrayType  *arr;
		int			ndims,
					nitems,
				   *dims;
		bits8	   *bitmap;

		Assert(PG_NARGS() == 1);

		/*
		 * If we get a null as VARIADIC array argument, we can't say anything
		 * useful about the number of elements, so return NULL.  This behavior
		 * is consistent with other variadic functions - see concat_internal.
		 */
		if (PG_ARGISNULL(0))
			return false;

		/*
		 * Non-null argument had better be an array.  We assume that any call
		 * context that could let get_fn_expr_variadic return true will have
		 * checked that a VARIADIC-labeled parameter actually is an array.  So
		 * it should be okay to just Assert that it's an array rather than
		 * doing a full-fledged error check.
		 */
		Assert(OidIsValid(get_base_element_type(get_fn_expr_argtype(fcinfo->flinfo, 0))));

		/* OK, safe to fetch the array value */
		arr = PG_GETARG_ARRAYTYPE_P(0);

		/* Count the array elements */
		ndims = ARR_NDIM(arr);
		dims = ARR_DIMS(arr);
		nitems = ArrayGetNItems(ndims, dims);

		/* Count those that are NULL */
		bitmap = ARR_NULLBITMAP(arr);
		if (bitmap)
		{
			int			bitmask = 1;

			for (i = 0; i < nitems; i++)
			{
				if ((*bitmap & bitmask) == 0)
					count++;

				bitmask <<= 1;
				if (bitmask == 0x100)
				{
					bitmap++;
					bitmask = 1;
				}
			}
		}

		*nargs = nitems;
		*nulls = count;
	}
	else
	{
		/* Separate arguments, so just count 'em */
		for (i = 0; i < PG_NARGS(); i++)
		{
			if (PG_ARGISNULL(i))
				count++;
		}

		*nargs = PG_NARGS();
		*nulls = count;
	}

	return true;
}

/*
 * makeWholeRowVar -
 *	  creates a Var node representing a whole row of the specified RTE
 *
 * A whole-row reference is a Var with varno set to the correct range
 * table entry, and varattno == 0 to signal that it references the whole
 * tuple.  (Use of zero here is unclean, since it could easily be confused
 * with error cases, but it's not worth changing now.)  The vartype indicates
 * a rowtype; either a named composite type, or RECORD.  This function
 * encapsulates the logic for determining the correct rowtype OID to use.
 *
 * If allowScalar is true, then for the case where the RTE is a function
 * returning a non-composite result type, we produce a normal Var referencing
 * the function's result directly, instead of the single-column composite
 * value that the whole-row notation might otherwise suggest.
 */
Var *
makeWholeRowVar(RangeTblEntry *rte,
				Index varno,
				Index varlevelsup,
				bool allowScalar)
{
	Var		   *result;
	Oid			toid;

	switch (rte->rtekind)
	{
		case RTE_RELATION:
			/* relation: the rowtype is a named composite type */
			toid = get_rel_type_id(rte->relid);
			if (!OidIsValid(toid))
				elog(ERROR, "could not find type OID for relation %u",
					 rte->relid);
			result = makeVar(varno,
							 InvalidAttrNumber,
							 toid,
							 -1,
							 InvalidOid,
							 varlevelsup);
			break;
		case RTE_FUNCTION:
			toid = exprType(rte->funcexpr);
			if (type_is_rowtype(toid))
			{
				/* func returns composite; same as relation case */
				result = makeVar(varno,
								 InvalidAttrNumber,
								 toid,
								 -1,
								 InvalidOid,
								 varlevelsup);
			}
			else if (allowScalar)
			{
				/* func returns scalar; just return its output as-is */
				result = makeVar(varno,
								 1,
								 toid,
								 -1,
								 exprCollation(rte->funcexpr),
								 varlevelsup);
			}
			else
			{
				/* func returns scalar, but we want a composite result */
				result = makeVar(varno,
								 InvalidAttrNumber,
								 RECORDOID,
								 -1,
								 InvalidOid,
								 varlevelsup);
			}
			break;
		default:

			/*
			 * RTE is a join, subselect, or VALUES.  We represent this as a
			 * whole-row Var of RECORD type. (Note that in most cases the Var
			 * will be expanded to a RowExpr during planning, but that is not
			 * our concern here.)
			 */
			result = makeVar(varno,
							 InvalidAttrNumber,
							 RECORDOID,
							 -1,
							 InvalidOid,
							 varlevelsup);
			break;
	}

	return result;
}

/*
 * Each database using a table space is isolated into its own name space
 * by a subdirectory named for the database OID.  On first creation of an
 * object in the tablespace, create the subdirectory.  If the subdirectory
 * already exists, fall through quietly.
 *
 * isRedo indicates that we are creating an object during WAL replay.
 * In this case we will cope with the possibility of the tablespace
 * directory not being there either --- this could happen if we are
 * replaying an operation on a table in a subsequently-dropped tablespace.
 * We handle this by making a directory in the place where the tablespace
 * symlink would normally be.  This isn't an exact replay of course, but
 * it's the best we can do given the available information.
 *
 * If tablespaces are not supported, we still need it in case we have to
 * re-create a database subdirectory (of $PGDATA/base) during WAL replay.
 */
void
TablespaceCreateDbspace(Oid spcNode, Oid dbNode, bool isRedo)
{
	struct stat st;
	char	   *dir;

	/*
	 * The global tablespace doesn't have per-database subdirectories, so
	 * nothing to do for it.
	 */
	if (spcNode == GLOBALTABLESPACE_OID)
		return;

	Assert(OidIsValid(spcNode));
	Assert(OidIsValid(dbNode));

	dir = GetDatabasePath(dbNode, spcNode);

	if (stat(dir, &st) < 0)
	{
		/* Directory does not exist? */
		if (errno == ENOENT)
		{
			/*
			 * Acquire TablespaceCreateLock to ensure that no DROP TABLESPACE
			 * or TablespaceCreateDbspace is running concurrently.
			 */
			LWLockAcquire(TablespaceCreateLock, LW_EXCLUSIVE);

			/*
			 * Recheck to see if someone created the directory while we were
			 * waiting for lock.
			 */
			if (stat(dir, &st) == 0 && S_ISDIR(st.st_mode))
			{
				/* Directory was created */
			}
			else
			{
				/* Directory creation failed? */
				if (mkdir(dir, S_IRWXU) < 0)
				{
					char	   *parentdir;

					/* Failure other than not exists or not in WAL replay? */
					if (errno != ENOENT || !isRedo)
						ereport(ERROR,
								(errcode_for_file_access(),
							  errmsg("could not create directory \"%s\": %m",
									 dir)));

					/*
					 * Parent directories are missing during WAL replay, so
					 * continue by creating simple parent directories rather
					 * than a symlink.
					 */

					/* create two parents up if not exist */
					parentdir = pstrdup(dir);
					get_parent_directory(parentdir);
					get_parent_directory(parentdir);
					/* Can't create parent and it doesn't already exist? */
					if (mkdir(parentdir, S_IRWXU) < 0 && errno != EEXIST)
						ereport(ERROR,
								(errcode_for_file_access(),
							  errmsg("could not create directory \"%s\": %m",
									 parentdir)));
					pfree(parentdir);

					/* create one parent up if not exist */
					parentdir = pstrdup(dir);
					get_parent_directory(parentdir);
					/* Can't create parent and it doesn't already exist? */
					if (mkdir(parentdir, S_IRWXU) < 0 && errno != EEXIST)
						ereport(ERROR,
								(errcode_for_file_access(),
							  errmsg("could not create directory \"%s\": %m",
									 parentdir)));
					pfree(parentdir);

					/* Create database directory */
					if (mkdir(dir, S_IRWXU) < 0)
						ereport(ERROR,
//.........这里部分代码省略.........

/*
 * Create a table space
 *
 * Only superusers can create a tablespace. This seems a reasonable restriction
 * since we're determining the system layout and, anyway, we probably have
 * root if we're doing this kind of activity
 */
Oid
CreateTableSpace(CreateTableSpaceStmt *stmt)
{
#ifdef HAVE_SYMLINK
	Relation	rel;
	Datum		values[Natts_pg_tablespace];
	bool		nulls[Natts_pg_tablespace];
	HeapTuple	tuple;
	Oid			tablespaceoid;
	char	   *location;
	Oid			ownerId;

	/* Must be super user */
	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 errmsg("permission denied to create tablespace \"%s\"",
						stmt->tablespacename),
				 errhint("Must be superuser to create a tablespace.")));

	/* However, the eventual owner of the tablespace need not be */
	if (stmt->owner)
		ownerId = get_role_oid(stmt->owner, false);
	else
		ownerId = GetUserId();

	/* Unix-ify the offered path, and strip any trailing slashes */
	location = pstrdup(stmt->location);
	canonicalize_path(location);

	/* disallow quotes, else CREATE DATABASE would be at risk */
	if (strchr(location, '\''))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_NAME),
				 errmsg("tablespace location cannot contain single quotes")));

	/*
	 * Allowing relative paths seems risky
	 *
	 * this also helps us ensure that location is not empty or whitespace
	 */
	if (!is_absolute_path(location))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
				 errmsg("tablespace location must be an absolute path")));

	/*
	 * Check that location isn't too long. Remember that we're going to append
	 * 'PG_XXX/<dboid>/<relid>.<nnn>'.	FYI, we never actually reference the
	 * whole path, but mkdir() uses the first two parts.
	 */
	if (strlen(location) + 1 + strlen(TABLESPACE_VERSION_DIRECTORY) + 1 +
		OIDCHARS + 1 + OIDCHARS + 1 + OIDCHARS > MAXPGPATH)
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
				 errmsg("tablespace location \"%s\" is too long",
						location)));

	/*
	 * Disallow creation of tablespaces named "pg_xxx"; we reserve this
	 * namespace for system purposes.
	 */
	if (!allowSystemTableMods && IsReservedName(stmt->tablespacename))
		ereport(ERROR,
				(errcode(ERRCODE_RESERVED_NAME),
				 errmsg("unacceptable tablespace name \"%s\"",
						stmt->tablespacename),
		errdetail("The prefix \"pg_\" is reserved for system tablespaces.")));

	/*
	 * Check that there is no other tablespace by this name.  (The unique
	 * index would catch this anyway, but might as well give a friendlier
	 * message.)
	 */
	if (OidIsValid(get_tablespace_oid(stmt->tablespacename, true)))
		ereport(ERROR,
				(errcode(ERRCODE_DUPLICATE_OBJECT),
				 errmsg("tablespace \"%s\" already exists",
						stmt->tablespacename)));

	/*
	 * Insert tuple into pg_tablespace.  The purpose of doing this first is to
	 * lock the proposed tablename against other would-be creators. The
	 * insertion will roll back if we find problems below.
	 */
	rel = heap_open(TableSpaceRelationId, RowExclusiveLock);

	MemSet(nulls, false, sizeof(nulls));

	values[Anum_pg_tablespace_spcname - 1] =
		DirectFunctionCall1(namein, CStringGetDatum(stmt->tablespacename));
	values[Anum_pg_tablespace_spcowner - 1] =
		ObjectIdGetDatum(ownerId);
//.........这里部分代码省略.........

/* Look up all of the information that SerializeTuple() and DeserializeTuple()
 * need to perform their jobs quickly.	Also, scratchpad space is allocated
 * for serialization and desrialization of datum values, and for formation/
 * deformation of tuples themselves.
 *
 * NOTE:  This function allocates various data-structures, but it assumes that
 *		  the current memory-context is acceptable.  So the caller should set
 *		  the desired memory-context before calling this function.
 */
void
InitSerTupInfo(TupleDesc tupdesc, SerTupInfo * pSerInfo)
{
	int			i,
				numAttrs;

	AssertArg(tupdesc != NULL);
	AssertArg(pSerInfo != NULL);

	if (s_tupSerMemCtxt == NULL)
	{
		/* Create tuple-serialization memory context. */
		s_tupSerMemCtxt =
			AllocSetContextCreate(TopMemoryContext,
								  "TupSerMemCtxt",
								  ALLOCSET_DEFAULT_INITSIZE,	/* always have some memory */
								  ALLOCSET_DEFAULT_INITSIZE,
								  ALLOCSET_DEFAULT_MAXSIZE);
	}

	/* Set contents to all 0, just to make things clean and easy. */
	memset(pSerInfo, 0, sizeof(SerTupInfo));

	/* Store the tuple-descriptor so we can use it later. */
	pSerInfo->tupdesc = tupdesc;

	pSerInfo->chunkCache.len = 0;
	pSerInfo->chunkCache.items = NULL;

	/*
	 * If we have some attributes, go ahead and prepare the information for
	 * each attribute in the descriptor.  Otherwise, we can return right away.
	 */
	numAttrs = tupdesc->natts;
	if (numAttrs <= 0)
		return;

	pSerInfo->myinfo = (SerAttrInfo *) palloc0(numAttrs * sizeof(SerAttrInfo));

	pSerInfo->values = (Datum *) palloc(numAttrs * sizeof(Datum));
	pSerInfo->nulls = (bool *) palloc(numAttrs * sizeof(bool));

	for (i = 0; i < numAttrs; i++)
	{
		SerAttrInfo *attrInfo = pSerInfo->myinfo + i;

		/*
		 * Get attribute's data-type Oid.  This lets us shortcut the comm
		 * operations for some attribute-types.
		 */
		attrInfo->atttypid = tupdesc->attrs[i]->atttypid;
		
		/*
		 * Ok, we want the Binary input/output routines for the type if they exist,
		 * else we want the normal text input/output routines.
		 * 
		 * User defined types might or might not have binary routines.
		 * 
		 * getTypeBinaryOutputInfo throws an error if we try to call it to get
		 * the binary output routine and one doesn't exist, so let's not call that.
		 */
		{
			HeapTuple	typeTuple;
			Form_pg_type pt;
			cqContext	*pcqCtx;

			pcqCtx = caql_beginscan(
					NULL,
					cql("SELECT * FROM pg_type "
						" WHERE oid = :1 ",
						ObjectIdGetDatum(attrInfo->atttypid)));

			typeTuple = caql_getnext(pcqCtx);

			if (!HeapTupleIsValid(typeTuple))
				elog(ERROR, "cache lookup failed for type %u", attrInfo->atttypid);
			pt = (Form_pg_type) GETSTRUCT(typeTuple);
		
			if (!pt->typisdefined)
				ereport(ERROR,
						(errcode(ERRCODE_UNDEFINED_OBJECT),
						 errmsg("type %s is only a shell",
								format_type_be(attrInfo->atttypid))));
								
			/* If we don't have both binary routines */
			if (!OidIsValid(pt->typsend) || !OidIsValid(pt->typreceive))
			{
				/* Use the normal text routines (slower) */
				if (!OidIsValid(pt->typoutput))
					ereport(ERROR,
						(errcode(ERRCODE_UNDEFINED_FUNCTION),
//.........这里部分代码省略.........

/*
 * Test property of an index AM, index, or index column.
 *
 * This is common code for different SQL-level funcs, so the amoid and
 * index_oid parameters are mutually exclusive; we look up the amoid from the
 * index_oid if needed, or if no index oid is given, we're looking at AM-wide
 * properties.
 */
static Datum
indexam_property(FunctionCallInfo fcinfo,
				 const char *propname,
				 Oid amoid, Oid index_oid, int attno)
{
	bool		res = false;
	bool		isnull = false;
	int			natts = 0;
	IndexAMProperty prop;
	IndexAmRoutine *routine;

	/* Try to convert property name to enum (no error if not known) */
	prop = lookup_prop_name(propname);

	/* If we have an index OID, look up the AM, and get # of columns too */
	if (OidIsValid(index_oid))
	{
		HeapTuple	tuple;
		Form_pg_class rd_rel;

		Assert(!OidIsValid(amoid));
		tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(index_oid));
		if (!HeapTupleIsValid(tuple))
			PG_RETURN_NULL();
		rd_rel = (Form_pg_class) GETSTRUCT(tuple);
		if (rd_rel->relkind != RELKIND_INDEX &&
			rd_rel->relkind != RELKIND_PARTITIONED_INDEX)
		{
			ReleaseSysCache(tuple);
			PG_RETURN_NULL();
		}
		amoid = rd_rel->relam;
		natts = rd_rel->relnatts;
		ReleaseSysCache(tuple);
	}

	/*
	 * At this point, either index_oid == InvalidOid or it's a valid index
	 * OID. Also, after this test and the one below, either attno == 0 for
	 * index-wide or AM-wide tests, or it's a valid column number in a valid
	 * index.
	 */
	if (attno < 0 || attno > natts)
		PG_RETURN_NULL();

	/*
	 * Get AM information.  If we don't have a valid AM OID, return NULL.
	 */
	routine = GetIndexAmRoutineByAmId(amoid, true);
	if (routine == NULL)
		PG_RETURN_NULL();

	/*
	 * If there's an AM property routine, give it a chance to override the
	 * generic logic.  Proceed if it returns false.
	 */
	if (routine->amproperty &&
		routine->amproperty(index_oid, attno, prop, propname,
							&res, &isnull))
	{
		if (isnull)
			PG_RETURN_NULL();
		PG_RETURN_BOOL(res);
	}

	if (attno > 0)
	{
		HeapTuple	tuple;
		Form_pg_index rd_index;
		bool		iskey = true;

		/*
		 * Handle column-level properties. Many of these need the pg_index row
		 * (which we also need to use to check for nonkey atts) so we fetch
		 * that first.
		 */
		tuple = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(index_oid));
		if (!HeapTupleIsValid(tuple))
			PG_RETURN_NULL();
		rd_index = (Form_pg_index) GETSTRUCT(tuple);

		Assert(index_oid == rd_index->indexrelid);
		Assert(attno > 0 && attno <= rd_index->indnatts);

		isnull = true;

		/*
		 * If amcaninclude, we might be looking at an attno for a nonkey
		 * column, for which we (generically) assume that most properties are
		 * null.
		 */
		if (routine->amcaninclude
//.........这里部分代码省略.........

/* ----------------------------------------------------------------
 *		ExecHashTableCreate
 *
 *		create an empty hashtable data structure for hashjoin.
 * ----------------------------------------------------------------
 */
HashJoinTable
ExecHashTableCreate(Hash *node, List *hashOperators, bool keepNulls)
{
	HashJoinTable hashtable;
	Plan	   *outerNode;
	int			nbuckets;
	int			nbatch;
	int			num_skew_mcvs;
	int			log2_nbuckets;
	int			nkeys;
	int			i;
	ListCell   *ho;
	MemoryContext oldcxt;

	/*
	 * Get information about the size of the relation to be hashed (it's the
	 * "outer" subtree of this node, but the inner relation of the hashjoin).
	 * Compute the appropriate size of the hash table.
	 */
	outerNode = outerPlan(node);

	ExecChooseHashTableSize(outerNode->plan_rows, outerNode->plan_width,
							OidIsValid(node->skewTable),
							&nbuckets, &nbatch, &num_skew_mcvs);

	/* nbuckets must be a power of 2 */
	log2_nbuckets = my_log2(nbuckets);
	Assert(nbuckets == (1 << log2_nbuckets));

	/*
	 * Initialize the hash table control block.
	 *
	 * The hashtable control block is just palloc'd from the executor's
	 * per-query memory context.  Everything else should be kept inside the
	 * subsidiary hashCxt or batchCxt.
	 */
	hashtable = (HashJoinTable) palloc(sizeof(HashJoinTableData));
	hashtable->nbuckets = nbuckets;
	hashtable->nbuckets_original = nbuckets;
	hashtable->nbuckets_optimal = nbuckets;
	hashtable->log2_nbuckets = log2_nbuckets;
	hashtable->log2_nbuckets_optimal = log2_nbuckets;
	hashtable->buckets = NULL;
	hashtable->keepNulls = keepNulls;
	hashtable->skewEnabled = false;
	hashtable->skewBucket = NULL;
	hashtable->skewBucketLen = 0;
	hashtable->nSkewBuckets = 0;
	hashtable->skewBucketNums = NULL;
	hashtable->nbatch = nbatch;
	hashtable->curbatch = 0;
	hashtable->nbatch_original = nbatch;
	hashtable->nbatch_outstart = nbatch;
	hashtable->growEnabled = true;
	hashtable->totalTuples = 0;
	hashtable->skewTuples = 0;
	hashtable->innerBatchFile = NULL;
	hashtable->outerBatchFile = NULL;
	hashtable->spaceUsed = 0;
	hashtable->spacePeak = 0;
	hashtable->spaceAllowed = work_mem * 1024L;
	hashtable->spaceUsedSkew = 0;
	hashtable->spaceAllowedSkew =
		hashtable->spaceAllowed * SKEW_WORK_MEM_PERCENT / 100;
	hashtable->chunks = NULL;

#ifdef HJDEBUG
	printf("Hashjoin %p: initial nbatch = %d, nbuckets = %d\n",
		   hashtable, nbatch, nbuckets);
#endif

	/*
	 * Create temporary memory contexts in which to keep the hashtable working
	 * storage.  See notes in executor/hashjoin.h.
	 */
	hashtable->hashCxt = AllocSetContextCreate(CurrentMemoryContext,
											   "HashTableContext",
											   ALLOCSET_DEFAULT_SIZES);

	hashtable->batchCxt = AllocSetContextCreate(hashtable->hashCxt,
												"HashBatchContext",
												ALLOCSET_DEFAULT_SIZES);

	/* Allocate data that will live for the life of the hashjoin */

	oldcxt = MemoryContextSwitchTo(hashtable->hashCxt);

	/*
	 * Get info about the hash functions to be used for each hash key. Also
	 * remember whether the join operators are strict.
	 */
	nkeys = list_length(hashOperators);
	hashtable->outer_hashfunctions =
		(FmgrInfo *) palloc(nkeys * sizeof(FmgrInfo));
//.........这里部分代码省略.........

/* ---------------------------------------------------------------------
 * CREATE PROCEDURAL LANGUAGE
 * ---------------------------------------------------------------------
 */
ObjectAddress
CreateProceduralLanguage(CreatePLangStmt *stmt)
{
	PLTemplate *pltemplate;
	ObjectAddress tmpAddr;
	Oid			handlerOid,
				inlineOid,
				valOid;
	Oid			funcrettype;
	Oid			funcargtypes[1];

	/*
	 * If we have template information for the language, ignore the supplied
	 * parameters (if any) and use the template information.
	 */
	if ((pltemplate = find_language_template(stmt->plname)) != NULL)
	{
		List	   *funcname;

		/*
		 * Give a notice if we are ignoring supplied parameters.
		 */
		if (stmt->plhandler)
			ereport(NOTICE,
					(errmsg("using pg_pltemplate information instead of CREATE LANGUAGE parameters")));

		/*
		 * Check permission
		 */
		if (!superuser())
		{
			if (!pltemplate->tmpldbacreate)
				ereport(ERROR,
						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
						 errmsg("must be superuser to create procedural language \"%s\"",
								stmt->plname)));
			if (!pg_database_ownercheck(MyDatabaseId, GetUserId()))
				aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_DATABASE,
							   get_database_name(MyDatabaseId));
		}

		/*
		 * Find or create the handler function, which we force to be in the
		 * pg_catalog schema.  If already present, it must have the correct
		 * return type.
		 */
		funcname = SystemFuncName(pltemplate->tmplhandler);
		handlerOid = LookupFuncName(funcname, 0, funcargtypes, true);
		if (OidIsValid(handlerOid))
		{
			funcrettype = get_func_rettype(handlerOid);
			if (funcrettype != LANGUAGE_HANDLEROID)
				ereport(ERROR,
						(errcode(ERRCODE_WRONG_OBJECT_TYPE),
				  errmsg("function %s must return type \"language_handler\"",
						 NameListToString(funcname))));
		}
		else
		{
			tmpAddr = ProcedureCreate(pltemplate->tmplhandler,
									  PG_CATALOG_NAMESPACE,
									  false,	/* replace */
									  false,	/* returnsSet */
									  LANGUAGE_HANDLEROID,
									  BOOTSTRAP_SUPERUSERID,
									  ClanguageId,
									  F_FMGR_C_VALIDATOR,
									  pltemplate->tmplhandler,
									  pltemplate->tmpllibrary,
									  false,	/* isAgg */
									  false,	/* isWindowFunc */
									  false,	/* security_definer */
									  false,	/* isLeakProof */
									  false,	/* isStrict */
									  PROVOLATILE_VOLATILE,
									  PROPARALLEL_UNSAFE,
									  buildoidvector(funcargtypes, 0),
									  PointerGetDatum(NULL),
									  PointerGetDatum(NULL),
									  PointerGetDatum(NULL),
									  NIL,
									  PointerGetDatum(NULL),
									  PointerGetDatum(NULL),
									  1,
									  0);
			handlerOid = tmpAddr.objectId;
		}

		/*
		 * Likewise for the anonymous block handler, if required; but we don't
		 * care about its return type.
		 */
		if (pltemplate->tmplinline)
		{
			funcname = SystemFuncName(pltemplate->tmplinline);
			funcargtypes[0] = INTERNALOID;
//.........这里部分代码省略.........

//.........这里部分代码省略.........
	values[Anum_pg_language_lanname - 1] = NameGetDatum(&langname);
	values[Anum_pg_language_lanowner - 1] = ObjectIdGetDatum(languageOwner);
	values[Anum_pg_language_lanispl - 1] = BoolGetDatum(true);
	values[Anum_pg_language_lanpltrusted - 1] = BoolGetDatum(trusted);
	values[Anum_pg_language_lanplcallfoid - 1] = ObjectIdGetDatum(handlerOid);
	values[Anum_pg_language_laninline - 1] = ObjectIdGetDatum(inlineOid);
	values[Anum_pg_language_lanvalidator - 1] = ObjectIdGetDatum(valOid);
	nulls[Anum_pg_language_lanacl - 1] = true;

	/* Check for pre-existing definition */
	oldtup = SearchSysCache1(LANGNAME, PointerGetDatum(languageName));

	if (HeapTupleIsValid(oldtup))
	{
		/* There is one; okay to replace it? */
		if (!replace)
			ereport(ERROR,
					(errcode(ERRCODE_DUPLICATE_OBJECT),
					 errmsg("language \"%s\" already exists", languageName)));
		if (!pg_language_ownercheck(HeapTupleGetOid(oldtup), languageOwner))
			aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_LANGUAGE,
						   languageName);

		/*
		 * Do not change existing ownership or permissions.  Note
		 * dependency-update code below has to agree with this decision.
		 */
		replaces[Anum_pg_language_lanowner - 1] = false;
		replaces[Anum_pg_language_lanacl - 1] = false;

		/* Okay, do it... */
		tup = heap_modify_tuple(oldtup, tupDesc, values, nulls, replaces);
		simple_heap_update(rel, &tup->t_self, tup);

		ReleaseSysCache(oldtup);
		is_update = true;
	}
	else
	{
		/* Creating a new language */
		tup = heap_form_tuple(tupDesc, values, nulls);
		simple_heap_insert(rel, tup);
		is_update = false;
	}

	/* Need to update indexes for either the insert or update case */
	CatalogUpdateIndexes(rel, tup);

	/*
	 * Create dependencies for the new language.  If we are updating an
	 * existing language, first delete any existing pg_depend entries.
	 * (However, since we are not changing ownership or permissions, the
	 * shared dependencies do *not* need to change, and we leave them alone.)
	 */
	myself.classId = LanguageRelationId;
	myself.objectId = HeapTupleGetOid(tup);
	myself.objectSubId = 0;

	if (is_update)
		deleteDependencyRecordsFor(myself.classId, myself.objectId, true);

	/* dependency on owner of language */
	if (!is_update)
		recordDependencyOnOwner(myself.classId, myself.objectId,
								languageOwner);

	/* dependency on extension */
	recordDependencyOnCurrentExtension(&myself, is_update);

	/* dependency on the PL handler function */
	referenced.classId = ProcedureRelationId;
	referenced.objectId = handlerOid;
	referenced.objectSubId = 0;
	recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);

	/* dependency on the inline handler function, if any */
	if (OidIsValid(inlineOid))
	{
		referenced.classId = ProcedureRelationId;
		referenced.objectId = inlineOid;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
	}

	/* dependency on the validator function, if any */
	if (OidIsValid(valOid))
	{
		referenced.classId = ProcedureRelationId;
		referenced.objectId = valOid;
		referenced.objectSubId = 0;
		recordDependencyOn(&myself, &referenced, DEPENDENCY_NORMAL);
	}

	/* Post creation hook for new procedural language */
	InvokeObjectPostCreateHook(LanguageRelationId, myself.objectId, 0);

	heap_close(rel, RowExclusiveLock);

	return myself;
}

/*
 * Given the result tuple descriptor for a function with OUT parameters,
 * replace any polymorphic columns (ANYELEMENT etc) with correct data types
 * deduced from the input arguments. Returns TRUE if able to deduce all types,
 * FALSE if not.
 */
static bool
resolve_polymorphic_tupdesc(TupleDesc tupdesc, oidvector *declared_args,
							Node *call_expr)
{
	int			natts = tupdesc->natts;
	int			nargs = declared_args->dim1;
	bool		have_anyelement_result = false;
	bool		have_anyarray_result = false;
	bool		have_anynonarray = false;
	bool		have_anyenum = false;
	Oid			anyelement_type = InvalidOid;
	Oid			anyarray_type = InvalidOid;
	Oid			anycollation;
	int			i;

	/* See if there are any polymorphic outputs; quick out if not */
	for (i = 0; i < natts; i++)
	{
		switch (tupdesc->attrs[i]->atttypid)
		{
			case ANYELEMENTOID:
				have_anyelement_result = true;
				break;
			case ANYARRAYOID:
				have_anyarray_result = true;
				break;
			case ANYNONARRAYOID:
				have_anyelement_result = true;
				have_anynonarray = true;
				break;
			case ANYENUMOID:
				have_anyelement_result = true;
				have_anyenum = true;
				break;
			default:
				break;
		}
	}
	if (!have_anyelement_result && !have_anyarray_result)
		return true;

	/*
	 * Otherwise, extract actual datatype(s) from input arguments.	(We assume
	 * the parser already validated consistency of the arguments.)
	 */
	if (!call_expr)
		return false;			/* no hope */

	for (i = 0; i < nargs; i++)
	{
		switch (declared_args->values[i])
		{
			case ANYELEMENTOID:
			case ANYNONARRAYOID:
			case ANYENUMOID:
				if (!OidIsValid(anyelement_type))
					anyelement_type = get_call_expr_argtype(call_expr, i);
				break;
			case ANYARRAYOID:
				if (!OidIsValid(anyarray_type))
					anyarray_type = get_call_expr_argtype(call_expr, i);
				break;
			default:
				break;
		}
	}

	/* If nothing found, parser messed up */
	if (!OidIsValid(anyelement_type) &a