Generate alter column migration statements

1 files changed, 59 insertions, 6 deletions

diff --git a/odb/relational/oracle/schema.cxx b/odb/relational/oracle/schema.cxx
index 34ede1c..024701c 100644
--- a/odb/relational/oracle/schema.cxx
+++ b/odb/relational/oracle/schema.cxx
@@ -344,6 +344,31 @@ namespace relational
       };
       entry<drop_index> drop_index_;
 
+      struct alter_column: relational::alter_column, context
+      {
+        alter_column (base const& x): base (x) {}
+
+        virtual void
+        traverse (sema_rel::alter_column& ac)
+        {
+          assert (ac.null_altered ());
+
+          // Relax (NULL) in pre and tighten (NOT NULL) in post.
+          //
+          if (pre_ != ac.null ())
+            return;
+
+          if (first_)
+            first_ = false;
+          else
+            os << "," << endl
+               << "          ";
+
+          os << quote_id (ac.name ()) << (ac.null () ? " NULL" : " NOT NULL");
+        }
+      };
+      entry<alter_column> alter_column_;
+
       struct alter_table_pre: relational::alter_table_pre, context
       {
         alter_table_pre (base const& x): base (x) {}
@@ -360,9 +385,23 @@ namespace relational
             alter_header (at.name ());
             os << "  ADD (";
 
-            instance<create_column> c (emitter (), stream (), format_);
-            trav_rel::unames n;
-            n >> c;
+            instance<create_column> cc (emitter (), stream (), format_);
+            trav_rel::unames n (*cc);
+            names (at, n);
+            os << ")" << endl;
+
+            post_statement ();
+          }
+
+          if (check_alter_null (at, true))
+          {
+            pre_statement ();
+            alter_header (at.name ());
+            os << "  MODIFY (";
+
+            bool tl (true); // (Im)perfect forwarding.
+            instance<alter_column> ac (emitter (), stream (), format_, tl);
+            trav_rel::unames n (*ac);
             names (at, n);
             os << ")" << endl;
 
@@ -388,9 +427,23 @@ namespace relational
             alter_header (at.name ());
             os << "  DROP (";
 
-            instance<drop_column> c (emitter (), stream (), format_);
-            trav_rel::unames n;
-            n >> c;
+            instance<drop_column> dc (emitter (), stream (), format_);
+            trav_rel::unames n (*dc);
+            names (at, n);
+            os << ")" << endl;
+
+            post_statement ();
+          }
+
+          if (check_alter_null (at, false))
+          {
+            pre_statement ();
+            alter_header (at.name ());
+            os << "  MODIFY (";
+
+            bool fl (false); // (Im)perfect forwarding.
+            instance<alter_column> ac (emitter (), stream (), format_, fl);
+            trav_rel::unames n (*ac);
             names (at, n);
             os << ")" << endl;