> Huh, I don't know where I got the idea you were (or someone else was?)

> in the position that attislocal should be reset.  I'll clean everything
> up and submit the patch I had originally made.

All right, this is it.  This patch merely checks if child tables have
the column.  If atttypid and atttypmod are the same, the attributes'
attinhcount is incremented; else the operation is aborted.  If child
tables don't have the column, recursively add it.

attislocal is not touched in any case.

Alvaro Herrera

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 14d82630c8adeed544e216fa829995a318d1d1ca..c66f0662b8d290fd6d2e110c0ce1ef4dd16ff5aa 100644 (file)
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.45 2002/09/28 20:00:19 tgl Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/commands/tablecmds.c,v 1.46 2002/10/19 02:09:45 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1643,22 +1643,53 @@ AlterTableAddColumn(Oid myrelid,
        colDefChild->inhcount = 1;
        colDefChild->is_local = false;
 
-       /* this routine is actually in the planner */
-       children = find_all_inheritors(myrelid);
+       /* we only need direct inheritors */
+       children = find_inheritance_children(myrelid);
 
        /*
-        * find_all_inheritors does the recursive search of the
-        * inheritance hierarchy, so all we have to do is process all of
-        * the relids in the list that it returns.
+        * If the child has a column with same name and type,
+        * increment its attinhcount and continue.  If it has
+        * different type, abort.  If it doesn't have a column
+        * with the same name, add it.
         */
        foreach(child, children)
        {
            Oid         childrelid = lfirsti(child);
+           HeapTuple   tuple;
+           Form_pg_attribute childatt;
 
            if (childrelid == myrelid)
                continue;
 
-           AlterTableAddColumn(childrelid, false, true, colDefChild);
+           attrdesc = heap_openr(AttributeRelationName, RowExclusiveLock);
+           tuple = SearchSysCacheCopyAttName(childrelid, colDef->colname);
+           if (!HeapTupleIsValid(tuple))
+           {
+               heap_close(attrdesc, RowExclusiveLock);
+               AlterTableAddColumn(childrelid, false, true, colDefChild);
+               continue;
+           }
+           childatt = (Form_pg_attribute) GETSTRUCT(tuple);
+
+           typeTuple = typenameType(colDef->typename);
+           tform = (Form_pg_type) GETSTRUCT(typeTuple);
+
+           if (HeapTupleGetOid(typeTuple) != childatt->atttypid ||
+                   colDef->typename->typemod != childatt->atttypmod)
+               elog(ERROR, "ALTER TABLE: child table %u has different "
+                       "type for column \"%s\"",
+                       childrelid, colDef->colname);
+
+           childatt->attinhcount++;
+           simple_heap_update(attrdesc, &tuple->t_self, tuple);
+           CatalogUpdateIndexes(attrdesc, tuple);
+           
+           elog(NOTICE, "ALTER TABLE: merging definition of column "
+                   "\"%s\" for child %u", colDef->colname, childrelid);
+
+           heap_close(attrdesc, RowExclusiveLock);
+           heap_freetuple(tuple);
+           ReleaseSysCache(typeTuple);
        }
    }
    else