Postgres95 1.01 Distribution - Virgin SourcesPG95-1_01

1 files changed, 123 insertions, 0 deletions

diff --git a/src/backend/optimizer/util/relnode.c b/src/backend/optimizer/util/relnode.c
new file mode 100644
index 00000000000..351fb182107
--- /dev/null
+++ b/src/backend/optimizer/util/relnode.c
@@ -0,0 +1,123 @@
+/*-------------------------------------------------------------------------
+ *
+ * relnode.c--
+ *    Relation manipulation routines
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *    $Header: /cvsroot/pgsql/src/backend/optimizer/util/relnode.c,v 1.1.1.1 1996/07/09 06:21:39 scrappy Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "nodes/relation.h"
+
+#include "optimizer/internal.h"
+#include "optimizer/pathnode.h"		/* where the decls go */
+#include "optimizer/plancat.h"
+
+
+
+/*    
+ * get_base_rel--
+ *    Returns relation entry corresponding to 'relid', creating a new one if
+ *    necessary. This is for base relations.
+ *    
+ */
+Rel *get_base_rel(Query* root, int relid)
+{
+    List *relids;
+    Rel *rel;
+
+    relids = lconsi(relid, NIL);
+    rel = rel_member(relids, root->base_relation_list_);
+    if (rel==NULL) {
+	rel = makeNode(Rel);
+	rel->relids = relids;
+	rel->indexed = false;
+	rel->pages =  0;
+	rel->tuples = 0;
+	rel->width = 0;
+	rel->targetlist = NIL;
+	rel->pathlist = NIL;
+	rel->unorderedpath = (Path *)NULL;
+	rel->cheapestpath = (Path *)NULL;
+	rel->pruneable = true;
+	rel->classlist = NULL;
+	rel->ordering = NULL;
+	rel->relam = InvalidOid;
+	rel->clauseinfo = NIL;
+	rel->joininfo = NIL;
+	rel->innerjoin = NIL;
+	rel->superrels = NIL;
+	
+	root->base_relation_list_ = lcons(rel,
+				    root->base_relation_list_);
+	
+	/*
+	 * ??? the old lispy C code (get_rel) do a listp(relid) here but
+	 * that can never happen since we already established relid is not
+	 * a list.				-ay 10/94
+	 */
+	if(relid < 0) {
+	    /*
+	     * If the relation is a materialized relation, assume 
+	     * constants for sizes.
+	     */
+	    rel->pages = _TEMP_RELATION_PAGES_;
+	    rel->tuples = _TEMP_RELATION_TUPLES_;
+	    
+	} else {
+	    bool hasindex;
+	    int pages, tuples;
+	    
+	    /*
+	     * Otherwise, retrieve relation characteristics from the
+	     * system catalogs.
+	     */
+	    relation_info(root, relid, &hasindex, &pages, &tuples);
+	    rel->indexed = hasindex;
+	    rel->pages = pages;
+	    rel->tuples = tuples;
+	} 
+    }
+    return rel;
+}
+
+/*    
+ * get_join_rel--
+ *    Returns relation entry corresponding to 'relid' (a list of relids),
+ *    creating a new one if necessary. This is for join relations.
+ *    
+ */
+Rel *get_join_rel(Query *root, List *relid)
+{
+    return rel_member(relid, root->join_relation_list_);
+}
+
+/*    
+ * rel-member--
+ *    Determines whether a relation of id 'relid' is contained within a list
+ *    'rels'.  
+ *    
+ * Returns the corresponding entry in 'rels' if it is there.
+ *    
+ */
+Rel *
+rel_member(List *relid, List *rels)
+{
+    List *temp = NIL;
+    List *temprelid = NIL;
+    
+    if (relid!=NIL && rels!=NIL) {
+	foreach(temp,rels) {
+	    temprelid = ((Rel*)lfirst(temp))->relids;
+	    if(same(temprelid, relid))   
+		return((Rel*)(lfirst(temp)));
+	}
+    } 
+    return(NULL);
+}