Support for versioning simple value in object

9 files changed, 663 insertions, 189 deletions

diff --git a/odb/context.cxx b/odb/context.cxx
index 5fc14d4..af07007 100644
--- a/odb/context.cxx
+++ b/odb/context.cxx
@@ -2402,6 +2402,9 @@ namespace
       if (discriminator (m))
         c_.discriminator++;
 
+      if (added (member_path_) || deleted (member_path_))
+        c_.soft++;
+
       if (separate_load (member_path_))
         c_.separate_load++;
 
diff --git a/odb/context.hxx b/odb/context.hxx
index df32cdd..9c52282 100644
--- a/odb/context.hxx
+++ b/odb/context.hxx
@@ -726,7 +726,7 @@ public:
     return m.count ("transient");
   }
 
-  // Return the deletion version or 0 if not fort-deleted.
+  // Return the deletion version or 0 if not soft-deleted.
   //
   static unsigned long long
   deleted (semantics::class_& c)
@@ -735,6 +735,12 @@ public:
   }
 
   static unsigned long long
+  deleted (semantics::data_member& m)
+  {
+    return m.get<unsigned long long> ("deleted", 0);
+  }
+
+  static unsigned long long
   deleted (data_member_path const& mp)
   {
     unsigned long long r (0);
@@ -745,7 +751,7 @@ public:
          i != mp.rend (); ++i)
     {
       unsigned long long v ((*i)->get<unsigned long long> ("deleted", 0));
-      if (v != 0 && v < r)
+      if (v != 0 && (r == 0 || v < r))
         r = v;
     }
 
@@ -755,6 +761,12 @@ public:
   // Return the addition version or 0 if not soft-added.
   //
   static unsigned long long
+  added (semantics::data_member& m)
+  {
+    return m.get<unsigned long long> ("added", 0);
+  }
+
+  static unsigned long long
   added (data_member_path const& mp)
   {
     unsigned long long r (0);
@@ -888,6 +900,26 @@ public:
     return unit.get<model_version> ("model-version");
   }
 
+  // Versioned object, view, or composite.
+  //
+  static bool
+  versioned (semantics::class_& c)
+  {
+    // Set by processor.
+    //
+    return c.count ("versioned") != 0;
+  }
+
+  // Versioned container.
+  //
+  static bool
+  versioned (semantics::data_member& m)
+  {
+    // Set by processor.
+    //
+    return container (m)->count ("versioned");
+  }
+
   // Object sections.
   //
   static object_section&
@@ -1145,6 +1177,7 @@ public:
           readonly (0),
           optimistic_managed (0),
           discriminator (0),
+          soft (0),
           separate_load (0),
           separate_update (0)
     {
@@ -1157,6 +1190,8 @@ public:
     size_t optimistic_managed;
     size_t discriminator;
 
+    size_t soft; // Soft-added/deleted.
+
     size_t separate_load;
     size_t separate_update; // Only readwrite.
   };
diff --git a/odb/processor.cxx b/odb/processor.cxx
index bc6c408..8c4efaf 100644
--- a/odb/processor.cxx
+++ b/odb/processor.cxx
@@ -1656,6 +1656,13 @@ namespace
           t.set ("key-tree-hint", kh);
           t.set ("key-not-null", true);
         }
+
+        // Check if we are versioned.
+        //
+        // @@ TODO
+        //
+        if (force_versioned)
+          t.set ("versioned", true);
       }
 
       // Process member data.
@@ -1896,12 +1903,16 @@ namespace
       if (k == class_object)
         traverse_object_pre (c);
       else if (k == class_view)
-        traverse_view (c);
+        traverse_view_pre (c);
 
       names (c);
 
       if (k == class_object)
         traverse_object_post (c);
+      else if (k == class_view)
+        traverse_view_post (c);
+      else if (k == class_composite)
+        traverse_composite_post (c);
     }
 
     //
@@ -2085,8 +2096,19 @@ namespace
     traverse_object_post (type& c)
     {
       semantics::class_* poly_root (polymorphic (c));
+      bool poly_derived (poly_root != 0 && poly_root != &c);
+
       semantics::data_member* opt (optimistic (c));
 
+      // Figure out if we are versioned. We are versioned if we have
+      // soft-added/deleted columns ourselves or our poly-base is
+      // versioned.
+      //
+      if (force_versioned ||
+          column_count (c).soft != 0 ||
+          (poly_derived && polymorphic_base (c).count ("versioned")))
+        c.set ("versioned", true);
+
       // Sections.
       //
       user_sections& uss (c.get<user_sections> ("user-sections"));
@@ -2149,7 +2171,7 @@ namespace
     //
 
     virtual void
-    traverse_view (type& c)
+    traverse_view_pre (type& c)
     {
       // Resolve referenced objects from tree nodes to semantic graph
       // nodes. Also populate maps and compute counts.
@@ -2258,6 +2280,31 @@ namespace
       }
     }
 
+    virtual void
+    traverse_view_post (type& c)
+    {
+      // Figure out if we are versioned. When versioning is forced, ignore
+      // it for native views.
+      //
+      if ((force_versioned &&
+           c.get<view_query> ("query").kind == view_query::condition) ||
+          column_count (c).soft != 0)
+        c.set ("versioned", true);
+    }
+
+    //
+    // Composite.
+    //
+
+    virtual void
+    traverse_composite_post (type& c)
+    {
+      // Figure out if we are versioned.
+      //
+      if (force_versioned || column_count (c).soft != 0)
+        c.set ("versioned", true);
+    }
+
     //
     // Assign object/view pointer.
     //
diff --git a/odb/relational/header.cxx b/odb/relational/header.cxx
index 9bf6f5e..f3df52b 100644
--- a/odb/relational/header.cxx
+++ b/odb/relational/header.cxx
@@ -26,6 +26,8 @@ traverse_object (type& c)
   bool abst (abstract (c));
   bool reuse_abst (abst && !poly);
 
+  bool versioned (context::versioned (c));
+
   string const& type (class_fq_name (c));
 
   // Sections.
@@ -237,10 +239,16 @@ traverse_object (type& c)
     // false).
     //
     os << "static bool" << endl
-       << "grow (image_type&, " << truncated_vector;
+       << "grow (image_type&," << endl
+       << truncated_vector;
+
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration&";
 
     if (poly_derived)
-      os << ", std::size_t = depth";
+      os << "," << endl
+         << "std::size_t = depth";
 
     os << ");"
        << endl;
@@ -259,7 +267,13 @@ traverse_object (type& c)
        << "std::size_t id_size," << endl;
 
   os << "image_type&," << endl
-     << db << "::statement_kind);"
+     << db << "::statement_kind";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration&";
+
+  os << ");"
      << endl;
 
   // bind (id_image_type)
@@ -275,16 +289,31 @@ traverse_object (type& c)
   // init (image, object)
   //
   os << "static " << (generate_grow ? "bool" : "void") << endl
-     << "init (image_type&, const object_type&, " << db << "::statement_kind);"
+     << "init (image_type&," << endl
+     << "const object_type&," << endl
+     << db << "::statement_kind";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration&";
+
+  os << ");"
      << endl;
 
   // init (object, image)
   //
   os << "static void" << endl
-     << "init (object_type&, const image_type&, database*";
+     << "init (object_type&," << endl
+     << "const image_type&," << endl
+     << "database*";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration&";
 
   if (poly_derived)
-    os << ", std::size_t = depth";
+    os << "," << endl
+       << "std::size_t = depth";
 
   os << ");"
      << endl;
@@ -325,7 +354,6 @@ traverse_object (type& c)
   }
 
   column_count_type const& cc (column_count (c));
-  bool versioned (force_versioned);
 
   // Statements typedefs.
   //
@@ -347,8 +375,6 @@ traverse_object (type& c)
          << "statements_type;"
          << endl
          << "typedef statements_type root_statements_type;"
-         << "typedef " << db << "::object_statements<object_type> " <<
-        "base_statements_type;"
          << endl;
   }
   else
@@ -610,17 +636,16 @@ traverse_object (type& c)
     // Load the object image.
     //
     os << "static bool" << endl
-       << "find_ (";
-
-    if (poly && !poly_derived)
-      os << "base_statements_type&, ";
-    else
-      os << "statements_type&, ";
+       << "find_ (statements_type&," << endl
+       << "const id_type*";
 
-    os << "const id_type*";
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration&";
 
     if (poly_derived && !abst)
-      os << ", std::size_t = depth";
+      os << "," << endl
+         << "std::size_t = depth";
 
     os << ");"
        << endl;
@@ -630,14 +655,8 @@ traverse_object (type& c)
     // id.
     //
     os << "static void" << endl
-       << "load_ (";
-
-    if (poly && !poly_derived)
-      os << "base_statements_type&," << endl;
-    else
-      os << "statements_type&," << endl;
-
-    os << "object_type&," << endl
+       << "load_ (statements_type&," << endl
+       << "object_type&," << endl
        << "bool reload = false";
 
     if (poly_derived)
@@ -877,6 +896,8 @@ traverse_view (type& c)
 void relational::header::class1::
 traverse_composite (type& c)
 {
+  bool versioned (context::versioned (c));
+
   string const& type (class_fq_name (c));
 
   os << "// " << class_name (c) << endl
@@ -913,27 +934,57 @@ traverse_composite (type& c)
   if (generate_grow)
   {
     os << "static bool" << endl
-       << "grow (image_type&, " << truncated_vector << ");"
+       << "grow (image_type&," << endl
+       << truncated_vector;
+
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration&";
+
+    os << ");"
        << endl;
   }
 
   // bind (image_type)
   //
   os << "static void" << endl
-     << "bind (" << bind_vector << ", image_type&, " <<
-    db << "::statement_kind);"
+     << "bind (" << bind_vector << "," << endl
+     << "image_type&," << endl
+     << db << "::statement_kind";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration&";
+
+  os << ");"
      << endl;
 
   // init (image, value)
   //
   os << "static " << (generate_grow ? "bool" : "void") << endl
-     << "init (image_type&, const value_type&, " << db << "::statement_kind);"
+     << "init (image_type&," << endl
+     << "const value_type&," << endl
+     << db << "::statement_kind";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration&";
+
+  os << ");"
      << endl;
 
   // init (value, image)
   //
   os << "static void" << endl
-     << "init (value_type&, const image_type&, database*);"
+     << "init (value_type&," << endl
+     << "const image_type&," << endl
+     << "database*";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration&";
+
+  os << ");"
      << endl;
 
   if (!has_a (c, test_container))
@@ -941,13 +992,26 @@ traverse_composite (type& c)
     // get_null (image)
     //
     os << "static bool" << endl
-       << "get_null (const image_type&);"
+       << "get_null (const image_type&";
+
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration&";
+
+    os << ");"
        << endl;
 
     // set_null (image)
     //
     os << "static void" << endl
-       << "set_null (image_type&, " << db << "::statement_kind);"
+       << "set_null (image_type&," << endl
+       << db << "::statement_kind";
+
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration&";
+
+    os << ");"
        << endl;
   }
 
diff --git a/odb/relational/header.hxx b/odb/relational/header.hxx
index 0620a98..4aab05c 100644
--- a/odb/relational/header.hxx
+++ b/odb/relational/header.hxx
@@ -324,7 +324,7 @@ namespace relational
             data_columns += value_columns;
           }
 
-          versioned = force_versioned;
+          versioned = context::versioned (m);
 
           // Store column counts for the source generator.
           //
diff --git a/odb/relational/inline.hxx b/odb/relational/inline.hxx
index 928982e..8bdf5a6 100644
--- a/odb/relational/inline.hxx
+++ b/odb/relational/inline.hxx
@@ -42,6 +42,27 @@ namespace relational
       virtual bool
       pre (member_info& mi)
       {
+        // If the member is soft- added or deleted, check the version.
+        //
+        unsigned long long av (added (mi.m));
+        unsigned long long dv (deleted (mi.m));
+        if (av != 0 || dv != 0)
+        {
+          os << "if (";
+
+          if (av != 0)
+            os << "svm >= schema_version_migration (" << av << "ULL, true)";
+
+          if (av != 0 || dv != 0)
+            os << " &&" << endl;
+
+          if (dv != 0)
+            os << "svm <= schema_version_migration (" << dv << "ULL, true)";
+
+          os << ")"
+             << "{";
+        }
+
         // If the whole value type is readonly, then set will never be
         // called with sk == statement_update.
         //
@@ -57,6 +78,13 @@ namespace relational
       }
 
       virtual void
+      post (member_info& mi)
+      {
+        if (added (mi.m) || deleted (mi.m))
+          os << "}";
+      }
+
+      virtual void
       traverse_composite (member_info& mi)
       {
         string traits ("composite_value_traits< " + mi.fq_type () + ", id_" +
@@ -64,9 +92,14 @@ namespace relational
 
         if (get_)
           os << "r = r && " << traits << "::get_null (" <<
-            "i." << mi.var << "value);";
+            "i." << mi.var << "value";
         else
-          os << traits << "::set_null (i." << mi.var << "value, sk);";
+          os << traits << "::set_null (i." << mi.var << "value, sk";
+
+        if (versioned (*composite (mi.t)))
+          os << ", svm";
+
+        os << ");";
       }
     };
 
@@ -94,9 +127,14 @@ namespace relational
           os << "if (sk == statement_insert)" << endl;
 
         if (get_)
-          os << "r = r && " << traits << "::get_null (i);";
+          os << "r = r && " << traits << "::get_null (i";
         else
-          os << traits << "::set_null (i, sk);";
+          os << traits << "::set_null (i, sk";
+
+        if (versioned (c))
+          os << ", svm";
+
+        os << ");";
       }
 
     protected:
@@ -373,14 +411,9 @@ namespace relational
         {
           os << "inline" << endl
              << "void " << traits << "::" << endl
-             << "load_ (";
-
-          if (poly && !poly_derived)
-            os << "base_statements_type&, ";
-          else
-            os << "statements_type&, ";
-
-          os << "object_type& obj, bool)"
+             << "load_ (statements_type&," << endl
+             << "object_type& obj," << endl
+             << "bool)"
              << "{"
              << "ODB_POTENTIALLY_UNUSED (obj);"
              << endl;
@@ -499,6 +532,8 @@ namespace relational
       virtual void
       traverse_composite (type& c)
       {
+        bool versioned (context::versioned (c));
+
         string const& type (class_fq_name (c));
         string traits ("access::composite_value_traits< " + type + ", id_" +
                        db.string () + " >");
@@ -513,9 +548,20 @@ namespace relational
           //
           os << "inline" << endl
              << "bool " << traits << "::" << endl
-             << "get_null (const image_type& i)"
-             << "{"
-             << "bool r (true);";
+             << "get_null (const image_type& i";
+
+          if (versioned)
+            os << "," << endl
+               << "const schema_version_migration& svm";
+
+          os << ")"
+             << "{";
+
+          if (versioned)
+            os << "ODB_POTENTIALLY_UNUSED (svm);"
+               << endl;
+
+          os << "bool r (true);";
 
           inherits (c, get_null_base_inherits_);
           names (c, get_null_member_names_);
@@ -527,10 +573,21 @@ namespace relational
           //
           os << "inline" << endl
              << "void " << traits << "::" << endl
-             << "set_null (image_type& i, " << db << "::statement_kind sk)"
+             << "set_null (image_type& i," << endl
+             << db << "::statement_kind sk";
+
+          if (versioned)
+            os << "," << endl
+               << "const schema_version_migration& svm";
+
+          os << ")"
              << "{"
-             << "ODB_POTENTIALLY_UNUSED (sk);"
-             << endl
+             << "ODB_POTENTIALLY_UNUSED (sk);";
+
+          if (versioned)
+            os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+          os << endl
              << "using namespace " << db << ";"
              << endl;
 
diff --git a/odb/relational/pgsql/source.cxx b/odb/relational/pgsql/source.cxx
index 7c5f2f6..a7834a2 100644
--- a/odb/relational/pgsql/source.cxx
+++ b/odb/relational/pgsql/source.cxx
@@ -304,15 +304,44 @@ namespace relational
           e = ostr.str ();
 
           if (var_override_.empty ())
+          {
             os << "// " << mi.m.name () << endl
                << "//" << endl;
 
+            // If the member is soft- added or deleted, check the version.
+            //
+            unsigned long long av (added (mi.m));
+            unsigned long long dv (deleted (mi.m));
+            if (av != 0 || dv != 0)
+            {
+              os << "if (";
+
+              if (av != 0)
+                os << "svm >= schema_version_migration (" << av << "ULL, true)";
+
+              if (av != 0 && dv != 0)
+                os << " &&" << endl;
+
+              if (dv != 0)
+                os << "svm <= schema_version_migration (" << dv << "ULL, true)";
+
+              os << ")"
+                 << "{";
+            }
+          }
+
           return true;
         }
 
         virtual void
         post (member_info& mi)
         {
+          if (var_override_.empty ())
+          {
+            if (added (mi.m) || deleted (mi.m))
+              os << "}";
+          }
+
           if (semantics::class_* c = composite (mi.t))
             index_ += column_count (*c).total;
           else
@@ -324,10 +353,10 @@ namespace relational
         {
           os << "if (composite_value_traits< " << mi.fq_type () <<
             ", id_pgsql >::grow (" << endl
-             << "i." << mi.var << "value, t + " << index_ << "UL))"
-             << "{"
+             << "i." << mi.var << "value, t + " << index_ << "UL" <<
+            (versioned (*composite (mi.t)) ? ", svm" : "") << "))" << endl
              << "grew = true;"
-             << "}";
+             << endl;
         }
 
         virtual void
diff --git a/odb/relational/source.cxx b/odb/relational/source.cxx
index 3805be2..6afff9c 100644
--- a/odb/relational/source.cxx
+++ b/odb/relational/source.cxx
@@ -49,6 +49,9 @@ traverse_object (type& c)
       (opt ? context::grow (*opt) : false);
   }
 
+  column_count_type const& cc (column_count (c));
+  bool versioned (context::versioned (c));
+
   // Schema name as a string literal or empty.
   //
   string schema_name (options.schema_name ()[db]);
@@ -58,7 +61,6 @@ traverse_object (type& c)
   string const& type (class_fq_name (c));
   string traits ("access::object_traits_impl< " + type + ", id_" +
                  db.string () + " >");
-  column_count_type const& cc (column_count (c));
 
   user_sections& uss (c.get<user_sections> ("user-sections"));
   user_sections* buss (poly_base != 0
@@ -230,16 +232,26 @@ traverse_object (type& c)
   if (generate_grow)
   {
     os << "bool " << traits << "::" << endl
-       << "grow (image_type& i, " << truncated_vector << " t";
+       << "grow (image_type& i," << endl
+       << truncated_vector << " t";
+
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration& svm";
 
     if (poly_derived)
-      os << ", std::size_t d";
+      os << "," << endl
+         << "std::size_t d";
 
     os << ")"
        << "{"
        << "ODB_POTENTIALLY_UNUSED (i);"
-       << "ODB_POTENTIALLY_UNUSED (t);"
-       << endl
+       << "ODB_POTENTIALLY_UNUSED (t);";
+
+    if (versioned)
+      os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+    os << endl
        << "bool grew (false);"
        << endl;
 
@@ -257,6 +269,7 @@ traverse_object (type& c)
          << "{"
          << "if (base_traits::grow (*i.base, " <<
         "t + " << cols << "UL" <<
+        (context::versioned (*poly_base) ? ", svm" : "") <<
         (poly_base != poly_root ? ", d" : "") << "))" << endl
          << "i.base->version++;"
          << "}";
@@ -283,10 +296,20 @@ traverse_object (type& c)
        << "std::size_t id_size," << endl;
 
   os << "image_type& i," << endl
-     << db << "::statement_kind sk)"
+     << db << "::statement_kind sk";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration& svm";
+
+  os << ")"
      << "{"
-     << "ODB_POTENTIALLY_UNUSED (sk);"
-     << endl
+     << "ODB_POTENTIALLY_UNUSED (sk);";
+
+  if (versioned)
+    os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+  os << endl
      << "using namespace " << db << ";"
      << endl;
 
@@ -336,12 +359,13 @@ traverse_object (type& c)
     os << "// " << class_name (*poly_base) << " base" << endl
        << "//" << endl
        << "if (sk == statement_select)" << endl
-       << "base_traits::";
+       << "base_traits::bind (b + n, ";
 
-    if (poly_base == poly_root)
-      os << "bind (b + n, *i.base, sk);";
-    else
-      os << "bind (b + n, id, id_size, *i.base, sk);";
+    if (poly_base != poly_root)
+      os << "id, id_size, ";
+
+    os << "*i.base, sk" <<
+      (context::versioned (*poly_base) ? ", svm" : "") << ");";
   }
 
   os << "}";
@@ -378,13 +402,24 @@ traverse_object (type& c)
   // init (image, object)
   //
   os << (generate_grow ? "bool " : "void ") << traits << "::" << endl
-     << "init (image_type& i, const object_type& o, " <<
-    db << "::statement_kind sk)"
+     << "init (image_type& i," << endl
+     << "const object_type& o," << endl
+     << db << "::statement_kind sk";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration& svm";
+
+  os << ")"
      << "{"
      << "ODB_POTENTIALLY_UNUSED (i);"
      << "ODB_POTENTIALLY_UNUSED (o);"
-     << "ODB_POTENTIALLY_UNUSED (sk);"
-     << endl
+     << "ODB_POTENTIALLY_UNUSED (sk);";
+
+  if (versioned)
+    os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+  os << endl
      << "using namespace " << db << ";"
      << endl;
 
@@ -411,17 +446,28 @@ traverse_object (type& c)
   // init (object, image)
   //
   os << "void " << traits << "::" << endl
-     << "init (object_type& o, const image_type& i, database* db";
+     << "init (object_type& o," << endl
+     << "const image_type& i," << endl
+     << "database* db";
+
+  if (versioned)
+    os << "," << endl
+       << "const schema_version_migration& svm";
 
   if (poly_derived)
-    os << ", std::size_t d";
+    os << "," << endl
+       << "std::size_t d";
 
   os << ")"
      << "{"
      << "ODB_POTENTIALLY_UNUSED (o);"
      << "ODB_POTENTIALLY_UNUSED (i);"
-     << "ODB_POTENTIALLY_UNUSED (db);"
-     << endl;
+     << "ODB_POTENTIALLY_UNUSED (db);";
+
+  if (versioned)
+    os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+  os << endl;
 
   if (poly_derived)
   {
@@ -429,6 +475,7 @@ traverse_object (type& c)
        << "//" << endl
        << "if (--d != 0)" << endl
        << "base_traits::init (o, *i.base, db" <<
+      (context::versioned (*poly_base) ? ", svm" : "") <<
       (poly_base != poly_root ? ", d" : "") << ");"
        << endl;
   }
@@ -477,8 +524,6 @@ traverse_object (type& c)
   if (reuse_abst)
     return;
 
-  bool versioned (force_versioned);
-
   //
   // Containers (concrete).
   //
@@ -1087,6 +1132,10 @@ traverse_object (type& c)
        << "throw abstract_class ();"
        << endl;
 
+  if (versioned)
+    os << "const schema_version_migration& svm (" <<
+      "db.schema_version_migration (" << schema_name << "));";
+
   os << db << "::connection& conn (" << endl
      << db << "::transaction::current ().connection ());"
      << "statements_type& sts (" << endl
@@ -1124,7 +1173,7 @@ traverse_object (type& c)
   if (generate_grow)
     os << "if (";
 
-  os << "init (im, obj, statement_insert)";
+  os << "init (im, obj, statement_insert" << (versioned ? ", svm" : "") << ")";
 
   if (generate_grow)
     os << ")" << endl
@@ -1154,7 +1203,7 @@ traverse_object (type& c)
   if (poly_derived)
     os << "idb.bind, idb.count, ";
 
-  os << "im, statement_insert);";
+  os << "im, statement_insert" << (versioned ? ", svm" : "") << ");";
 
   if (poly_derived)
     os << "sts.insert_id_binding_version (idb.version);";
@@ -1440,6 +1489,11 @@ traverse_object (type& c)
            << "}";
       }
 
+      if (versioned && update_columns != 0)
+        os << "const schema_version_migration& svm (" <<
+          "db.schema_version_migration (" << schema_name << "));"
+           << endl;
+
       if (poly_derived)
       {
         bool readonly_base (context::readonly (*poly_base));
@@ -1507,7 +1561,8 @@ traverse_object (type& c)
           if (generate_grow)
             os << "if (";
 
-          os << "init (im, obj, statement_update)";
+          os << "init (im, obj, statement_update" <<
+            (versioned ? ", svm" : "") << ")";
 
           if (generate_grow)
             os << ")" << endl
@@ -1521,7 +1576,8 @@ traverse_object (type& c)
              << "im.version != sts.update_image_version () ||" << endl
              << "imb.version == 0)"
              << "{"
-             << "bind (imb.bind, idb.bind, idb.count, im, statement_update);"
+             << "bind (imb.bind, idb.bind, idb.count, im, statement_update" <<
+            (versioned ? ", svm" : "") << ");"
              << "sts.update_id_binding_version (idb.version);"
              << "sts.update_image_version (im.version);"
              << "imb.version++;"
@@ -1590,7 +1646,8 @@ traverse_object (type& c)
         if (generate_grow)
           os << "if (";
 
-        os << "init (im, obj, statement_update)";
+        os << "init (im, obj, statement_update" <<
+          (versioned ? ", svm" : "") << ")";
 
         if (generate_grow)
           os << ")" << endl
@@ -1599,7 +1656,7 @@ traverse_object (type& c)
         os << ";"
            << endl;
 
-        // Update binding is bound to two images (object and id)
+        // The update binding is bound to two images (object and id)
         // so we have to track both versions.
         //
         os << "bool u (false);" // Avoid incrementing version twice.
@@ -1607,7 +1664,8 @@ traverse_object (type& c)
            << "if (im.version != sts.update_image_version () ||" << endl
            << "imb.version == 0)"
            << "{"
-           << "bind (imb.bind, im, statement_update);"
+           << "bind (imb.bind, im, statement_update" <<
+          (versioned ? ", svm" : "") << ");"
            << "sts.update_image_version (im.version);"
            << "imb.version++;"
            << "u = true;"
@@ -2382,8 +2440,10 @@ traverse_object (type& c)
 
     os << "}";
 
-    // Get the connection.
-    //
+    if (versioned)
+      os << "const schema_version_migration& svm (" <<
+        "db.schema_version_migration (" << schema_name << "));";
+
     os << db << "::connection& conn (" << endl
        << db << "::transaction::current ().connection ());"
        << "statements_type& sts (" << endl
@@ -2404,7 +2464,7 @@ traverse_object (type& c)
     os << endl
        << "if (l.locked ())"
        << "{"
-       << "if (!find_ (sts, &id))" << endl
+       << "if (!find_ (sts, &id" << (versioned ? ", svm" : "") << "))" << endl
        << "return pointer_type ();";
 
     if (delay_freeing_statement_result)
@@ -2486,7 +2546,7 @@ traverse_object (type& c)
     else
       os << "callback (db, obj, callback_event::pre_load);";
 
-    os << "init (obj, sts.image (), &db);";
+    os << "init (obj, sts.image (), &db" << (versioned ? ", svm" : "") << ");";
 
     init_value_extra ();
 
@@ -2506,7 +2566,7 @@ traverse_object (type& c)
          << "pi.dispatch (info_type::call_load, db, &obj, &d);"
          << "}";
 
-    os << rsts << ".load_delayed ();"
+    os << rsts << ".load_delayed (" << (versioned ? "&svm" : "0") << ");"
        << "l.unlock ();";
 
     if (poly)
@@ -2573,6 +2633,10 @@ traverse_object (type& c)
 
     if (!abst)
     {
+      if (versioned)
+        os << "const schema_version_migration& svm (" <<
+          "db.schema_version_migration (" << schema_name << "));";
+
       os << db << "::connection& conn (" << endl
          << db << "::transaction::current ().connection ());"
          << "statements_type& sts (" << endl
@@ -2587,7 +2651,8 @@ traverse_object (type& c)
          << "statements_type::auto_lock l (" << rsts << ");"
          << endl;
 
-      os << "if (!find_ (sts, &id))" << endl
+      os << "if (!find_ (sts, &id" <<
+        (versioned ? ", svm" : "") << "))" << endl
          << "return false;"
          << endl;
 
@@ -2604,7 +2669,8 @@ traverse_object (type& c)
          << "reference_cache_traits::insert_guard ig (pos);"
          << endl
          << "callback (db, obj, callback_event::pre_load);"
-         << "init (obj, sts.image (), &db);";
+         << "init (obj, sts.image (), &db" <<
+        (versioned ? ", svm" : "") << ");";
 
       init_value_extra ();
 
@@ -2612,7 +2678,7 @@ traverse_object (type& c)
         os << "ar.free ();";
 
       os << "load_ (sts, obj);"
-         << rsts << ".load_delayed ();"
+         << rsts << ".load_delayed (" << (versioned ? "&svm" : "0") << ");"
          << "l.unlock ();"
          << "callback (db, obj, callback_event::post_load);"
          << "reference_cache_traits::load (pos);"
@@ -2673,6 +2739,10 @@ traverse_object (type& c)
 
     if (!abst)
     {
+      if (versioned)
+        os << "const schema_version_migration& svm (" <<
+          "db.schema_version_migration (" << schema_name << "));";
+
       os << db << "::connection& conn (" << endl
          << db << "::transaction::current ().connection ());"
          << "statements_type& sts (" << endl
@@ -2694,7 +2764,8 @@ traverse_object (type& c)
          << id_ma->translate ("obj") << ");"
          << endl;
 
-      os << "if (!find_ (sts, &id))" << endl
+      os << "if (!find_ (sts, &id" <<
+        (versioned ? ", svm" : "") << "))" << endl
          << "return false;"
          << endl;
 
@@ -2720,7 +2791,8 @@ traverse_object (type& c)
       }
 
       os << "callback (db, obj, callback_event::pre_load);"
-         << "init (obj, sts.image (), &db);";
+         << "init (obj, sts.image (), &db" <<
+        (versioned ? ", svm" : "") << ");";
 
       init_value_extra ();
 
@@ -2728,7 +2800,7 @@ traverse_object (type& c)
         os << "ar.free ();";
 
       os << "load_ (sts, obj, true);"
-         << rsts << ".load_delayed ();"
+         << rsts << ".load_delayed (" << (versioned ? "&svm" : "0") << ");"
          << "l.unlock ();"
          << "callback (db, obj, callback_event::post_load);"
          << "return true;";
@@ -3043,17 +3115,16 @@ traverse_object (type& c)
   if (id != 0)
   {
     os << "bool " << traits << "::" << endl
-       << "find_ (";
+       << "find_ (statements_type& sts," << endl
+       << "const id_type* id";
 
-    if (poly && !poly_derived)
-      os << "base_statements_type& sts, ";
-    else
-      os << "statements_type& sts, ";
-
-    os << "const id_type* id";
+    if (versioned)
+      os << "," << endl
+         << "const schema_version_migration& svm";
 
     if (poly_derived && !abst)
-      os << ", std::size_t d";
+      os << "," << endl
+         << "std::size_t d";
 
     os << ")"
        << "{"
@@ -3095,7 +3166,8 @@ traverse_object (type& c)
       os << "if (imb.version == 0 ||" << endl
          << "check_version (sts.select_image_versions (), im))"
          << "{"
-         << "bind (imb.bind, 0, 0, im, statement_select);"
+         << "bind (imb.bind, 0, 0, im, statement_select" <<
+        (versioned ? ", svm" : "") << ");"
          << "update_version (sts.select_image_versions ()," << endl
          << "im," << endl
          << "sts.select_image_bindings ());"
@@ -3106,7 +3178,8 @@ traverse_object (type& c)
       os << "if (im.version != sts.select_image_version () ||" << endl
          << "imb.version == 0)"
          << "{"
-         << "bind (imb.bind, im, statement_select);"
+         << "bind (imb.bind, im, statement_select" <<
+        (versioned ? ", svm" : "") << ");"
          << "sts.select_image_version (im.version);"
          << "imb.version++;"
          << "}";
@@ -3124,6 +3197,7 @@ traverse_object (type& c)
       os << "if (r == select_statement::truncated)"
          << "{"
          << "if (grow (im, sts.select_image_truncated ()" <<
+        (versioned ? ", svm" : "") <<
         (poly_derived ? (abst ? ", depth" : ", d") : "") << "))" << endl
          << "im.version++;"
          << endl;
@@ -3132,7 +3206,8 @@ traverse_object (type& c)
       {
         os << "if (check_version (sts.select_image_versions (), im))"
            << "{"
-           << "bind (imb.bind, 0, 0, im, statement_select);"
+           << "bind (imb.bind, 0, 0, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "update_version (sts.select_image_versions ()," << endl
            << "im," << endl
            << "sts.select_image_bindings ());"
@@ -3143,7 +3218,8 @@ traverse_object (type& c)
       {
         os << "if (im.version != sts.select_image_version ())"
            << "{"
-           << "bind (imb.bind, im, statement_select);"
+           << "bind (imb.bind, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "sts.select_image_version (im.version);"
            << "imb.version++;"
            << "st.refetch ();"
@@ -3183,14 +3259,8 @@ traverse_object (type& c)
                  (poly ? user_sections::count_load_empty : 0)) != 0)
   {
     os << "void " << traits << "::" << endl
-       << "load_ (";
-
-    if (poly && !poly_derived)
-      os << "base_statements_type& sts," << endl;
-    else
-      os << "statements_type& sts," << endl;
-
-    os << "object_type& obj," << endl
+       << "load_ (statements_type& sts," << endl
+       << "object_type& obj," << endl
        << "bool reload";
 
     if (poly_derived)
@@ -3309,7 +3379,12 @@ traverse_object (type& c)
       os << "if (d > " << (poly_depth - empty_depth) << "UL)"
          << "{";
 
-    os << "if (!find_ (sts, 0, d))" << endl
+    if (versioned)
+      os << "const schema_version_migration& svm (" <<
+        "db.schema_version_migration (" << schema_name << "));"
+         << endl;
+
+    os << "if (!find_ (sts, 0" << (versioned ? ", svm" : "") << ", d))" << endl
        << "throw object_not_persistent ();" // Database inconsistency.
        << endl;
 
@@ -3320,7 +3395,8 @@ traverse_object (type& c)
     if (delay_freeing_statement_result)
       os << "auto_result ar (st);";
 
-    os << "init (obj, sts.image (), &db, d);";
+    os << "init (obj, sts.image (), &db" << (versioned ? ", svm" : "") <<
+      ", d);";
 
     init_value_extra ();
 
@@ -3507,13 +3583,20 @@ traverse_object (type& c)
       //
       os << "result< " << traits << "::object_type >" << endl
          << traits << "::" << endl
-         << "query (database&, const query_base_type& q)"
+         << "query (database& db, const query_base_type& q)"
          << "{"
+         << "ODB_POTENTIALLY_UNUSED (db);"
+         << endl
          << "using namespace " << db << ";"
          << "using odb::details::shared;"
          << "using odb::details::shared_ptr;"
-         << endl
-         << db << "::connection& conn (" << endl
+         << endl;
+
+      if (versioned)
+        os << "const schema_version_migration& svm (" <<
+          "db.schema_version_migration (" << schema_name << "));";
+
+      os << db << "::connection& conn (" << endl
          << db << "::transaction::current ().connection ());"
          << endl
          << "statements_type& sts (" << endl
@@ -3532,7 +3615,8 @@ traverse_object (type& c)
         os << "if (imb.version == 0 ||" << endl
            << "check_version (sts.select_image_versions (), im))"
            << "{"
-           << "bind (imb.bind, 0, 0, im, statement_select);"
+           << "bind (imb.bind, 0, 0, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "update_version (sts.select_image_versions ()," << endl
            << "im," << endl
            << "sts.select_image_bindings ());"
@@ -3543,7 +3627,8 @@ traverse_object (type& c)
         os << "if (im.version != sts.select_image_version () ||" << endl
            << "imb.version == 0)"
            << "{"
-           << "bind (imb.bind, im, statement_select);"
+           << "bind (imb.bind, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "sts.select_image_version (im.version);"
            << "imb.version++;"
            << "}";
@@ -3569,7 +3654,7 @@ traverse_object (type& c)
       os << endl
          << "shared_ptr< odb::" << result_type << " > r (" << endl
          << "new (shared) " << db << "::" << result_type << " (" << endl
-         << "q, st, sts));"
+         << "q, st, sts, " << (versioned ? "&svm" : "0") << "));"
          << endl
          << "return result<object_type> (r);"
          << "}";
@@ -3633,8 +3718,14 @@ traverse_object (type& c)
          << "using namespace " << db << ";"
          << "using odb::details::shared;"
          << "using odb::details::shared_ptr;"
-         << endl
-         << db << "::connection& conn (" << endl
+         << endl;
+
+      if (versioned)
+        os << "const schema_version_migration& svm (" << endl
+           << "c.database ().schema_version_migration (" <<
+          schema_name << "));";
+
+      os << db << "::connection& conn (" << endl
          << "static_cast<" << db << "::connection&> (c));"
          << endl
          << "statements_type& sts (" << endl
@@ -3653,7 +3744,8 @@ traverse_object (type& c)
         os << "if (imb.version == 0 ||" << endl
            << "check_version (sts.select_image_versions (), im))"
            << "{"
-           << "bind (imb.bind, 0, 0, im, statement_select);"
+           << "bind (imb.bind, 0, 0, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "update_version (sts.select_image_versions ()," << endl
            << "im," << endl
            << "sts.select_image_bindings ());"
@@ -3664,7 +3756,8 @@ traverse_object (type& c)
         os << "if (im.version != sts.select_image_version () ||" << endl
            << "imb.version == 0)"
            << "{"
-           << "bind (imb.bind, im, statement_select);"
+           << "bind (imb.bind, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "sts.select_image_version (im.version);"
            << "imb.version++;"
            << "}";
@@ -3717,8 +3810,13 @@ traverse_object (type& c)
          << "shared_ptr<select_statement> st (" << endl
          << "odb::details::inc_ref (" << endl
          << "static_cast<select_statement*> (pq.stmt.get ())));"
-         << endl
-         << db << "::connection& conn (" << endl
+         << endl;
+
+      if (versioned)
+        os << "const schema_version_migration& svm (" <<
+          "db.schema_version_migration (" << schema_name << "));";
+
+      os << db << "::connection& conn (" << endl
          << db << "::transaction::current ().connection ());"
          << endl
          << "// The connection used by the current transaction and the" << endl
@@ -3742,7 +3840,8 @@ traverse_object (type& c)
         os << "if (imb.version == 0 ||" << endl
            << "check_version (sts.select_image_versions (), im))"
            << "{"
-           << "bind (imb.bind, 0, 0, im, statement_select);"
+           << "bind (imb.bind, 0, 0, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "update_version (sts.select_image_versions ()," << endl
            << "im," << endl
            << "sts.select_image_bindings ());"
@@ -3753,7 +3852,8 @@ traverse_object (type& c)
         os << "if (im.version != sts.select_image_version () ||" << endl
            << "imb.version == 0)"
            << "{"
-           << "bind (imb.bind, im, statement_select);"
+           << "bind (imb.bind, im, statement_select" <<
+          (versioned ? ", svm" : "") << ");"
            << "sts.select_image_version (im.version);"
            << "imb.version++;"
            << "}";
@@ -3766,7 +3866,7 @@ traverse_object (type& c)
       os << endl
          << "return shared_ptr<result_impl> (" << endl
          << "new (shared) " << db << "::" << result_type << " (" << endl
-         << "pq.query, st, sts));"
+         << "pq.query, st, sts, " << (versioned ? "&svm" : "0") << "));"
          << "}";
     }
   }
@@ -3870,13 +3970,11 @@ traverse_view (type& c)
   view_query& vq (c.get<view_query> ("query"));
 
   // Only process the view query if it is versioned since the query text
-  // (e.g., in the native view) must be structured. Also, we probably
-  // shouldn't try to optimize JOINs since the objects are JOINed
-  // explicitly by the user, unless we are adding poly-bases/derived.
-  //
-  // When versioning is forced, don't do it for native views.
+  // (e.g., in the native view) must be structured. We also shouldn't try
+  // to optimize JOINs (since the objects are JOINed explicitly by the
+  // user), unless we are adding poly-base/derived JOINs.
   //
-  bool versioned (force_versioned && vq.kind == view_query::condition);
+  bool versioned (context::versioned (c));
   bool query_optimize (false);
 
   string const& type (class_fq_name (c));
diff --git a/odb/relational/source.hxx b/odb/relational/source.hxx
index aae34da..0db2cb4 100644
--- a/odb/relational/source.hxx
+++ b/odb/relational/source.hxx
@@ -1001,6 +1001,27 @@ namespace relational
               os << "if (sk != statement_update)"
                  << "{";
           }
+
+          // If the member is soft- added or deleted, check the version.
+          //
+          unsigned long long av (added (mi.m));
+          unsigned long long dv (deleted (mi.m));
+          if (av != 0 || dv != 0)
+          {
+            os << "if (";
+
+            if (av != 0)
+              os << "svm >= schema_version_migration (" << av << "ULL, true)";
+
+            if (av != 0 && dv != 0)
+              os << " &&" << endl;
+
+            if (dv != 0)
+              os << "svm <= schema_version_migration (" << dv << "ULL, true)";
+
+            os << ")"
+               << "{";
+          }
         }
 
         return true;
@@ -1011,9 +1032,13 @@ namespace relational
       {
         if (var_override_.empty ())
         {
-          semantics::class_* c;
+          // We need to increment the index even if we skipped this
+          // member due to the schema version.
+          //
+          if (added (mi.m) || deleted (mi.m))
+            os << "}";
 
-          if ((c = composite (mi.t)))
+          if (semantics::class_* c = composite (mi.t))
           {
             bool ro (readonly (*c));
             column_count_type const& cc (column_count (*c));
@@ -1083,7 +1108,8 @@ namespace relational
       {
         os << "composite_value_traits< " << mi.fq_type () << ", id_" <<
           db << " >::bind (" << endl
-           << "b + n, " << arg << "." << mi.var << "value, sk);";
+           << "b + n, " << arg << "." << mi.var << "value, sk" <<
+          (versioned (*composite (mi.t)) ? ", svm" : "") << ");";
       }
 
     protected:
@@ -1123,7 +1149,8 @@ namespace relational
         else
           os << "composite_value_traits< ";
 
-        os << class_fq_name (c) << ", id_" << db << " >::bind (b + n, i, sk);";
+        os << class_fq_name (c) << ", id_" << db << " >::bind (b + n, i, sk" <<
+          (versioned (c) ? ", svm" : "") << ");";
 
         column_count_type const& cc (column_count (c));
 
@@ -1218,7 +1245,8 @@ namespace relational
           os << "composite_value_traits< ";
 
         os << class_fq_name (c) << ", id_" << db << " >::grow (" << endl
-           << "i, t + " << index_ << "UL))" << endl
+           << "i, t + " << index_ << "UL" <<
+          (versioned (c) ? ", svm" : "") << "))" << endl
            << "grew = true;"
            << endl;
 
@@ -1299,7 +1327,7 @@ namespace relational
         if (mi.ptr != 0 && mi.m.count ("polymorphic-ref"))
           return false;
 
-        bool comp (composite (mi.t));
+        semantics::class_* comp (composite (mi.t));
 
         if (!member_override_.empty ())
         {
@@ -1323,17 +1351,36 @@ namespace relational
           os << "// " << mi.m.name () << endl
              << "//" << endl;
 
+          // If the member is soft- added or deleted, check the version.
+          //
+          unsigned long long av (added (mi.m));
+          unsigned long long dv (deleted (mi.m));
+          if (av != 0 || dv != 0)
+          {
+            os << "if (";
+
+            if (av != 0)
+              os << "svm >= schema_version_migration (" << av << "ULL, true)";
+
+            if (av != 0 && dv != 0)
+              os << " &&" << endl;
+
+            if (dv != 0)
+              os << "svm <= schema_version_migration (" << dv << "ULL, true)";
+
+            os << ")"
+               << "{";
+          }
+
           // If the whole class is readonly, then we will never be
           // called with sk == statement_update.
           //
           if (!readonly (*context::top_object))
           {
-            semantics::class_* c;
-
             if (id (mi.m) ||
                 readonly (mi.m) ||
                 (section_ == 0 && separate_update (mi.m)) ||
-                ((c = composite (mi.t)) && readonly (*c))) // Can't be id.
+                (comp != 0 && readonly (*comp))) // Can't be id.
             {
               // If we are generating section init(), then sk can only be
               // statement_update.
@@ -1356,7 +1403,7 @@ namespace relational
             // Make sure this kind of member can be accessed with this
             // kind of accessor (database-specific, e.g., streaming).
             //
-            if (!comp)
+            if (comp == 0)
               check_accessor (mi, ma);
 
             // If this is not a synthesized expression, then output
@@ -1381,7 +1428,7 @@ namespace relational
         // For simple values this is taken care of by the value_traits
         // specializations.
         //
-        if (mi.wrapper != 0 && comp)
+        if (mi.wrapper != 0 && comp != 0)
         {
           // The wrapper type, not the wrapped type.
           //
@@ -1397,7 +1444,8 @@ namespace relational
               member << "))" << endl
                << "composite_value_traits< " << mi.fq_type () << ", id_" <<
               db << " >::set_null (" << endl
-               << "i." << mi.var << "value, sk);"
+               << "i." << mi.var << "value, sk" <<
+              (versioned (*comp) ? ", svm" : "") << ");"
                << "else"
                << "{";
           }
@@ -1456,7 +1504,7 @@ namespace relational
 
           member = "id";
         }
-        else if (comp)
+        else if (comp != 0)
           type = mi.fq_type ();
         else
         {
@@ -1467,7 +1515,7 @@ namespace relational
           os << "bool is_null (" << null (mi.m, key_prefix_) << ");";
         }
 
-        if (comp)
+        if (comp != 0)
           traits = "composite_value_traits< " + type + ", id_" +
             db.string () + " >";
         else
@@ -1484,6 +1532,8 @@ namespace relational
       virtual void
       post (member_info& mi)
       {
+        semantics::class_* comp (composite (mi.t));
+
         if (mi.ptr != 0)
         {
           os << "}"
@@ -1491,13 +1541,14 @@ namespace relational
 
           if (!null (mi.m, key_prefix_))
             os << "throw null_pointer ();";
-          else if (composite (mi.t))
-            os << traits << "::set_null (i." << mi.var << "value, sk);";
+          else if (comp != 0)
+            os << traits << "::set_null (i." << mi.var << "value, sk" <<
+              (versioned (*comp) ? ", svm" : "") << ");";
           else
             set_null (mi);
         }
 
-        if (mi.wrapper != 0 && composite (mi.t))
+        if (mi.wrapper != 0 && comp != 0)
         {
           if (null (mi.m, key_prefix_) &&
               mi.wrapper->template get<bool> ("wrapper-null-handler"))
@@ -1505,6 +1556,12 @@ namespace relational
         }
 
         os << "}";
+
+        if (member_override_.empty ())
+        {
+          if (added (mi.m) || deleted (mi.m))
+            os << "}";
+        }
       }
 
       virtual void
@@ -1518,7 +1575,13 @@ namespace relational
         os << traits << "::init (" << endl
            << "i." << mi.var << "value," << endl
            << member << "," << endl
-           << "sk)";
+           << "sk";
+
+        if (versioned (*composite (mi.t)))
+          os << "," << endl
+             << "svm";
+
+        os << ")";
 
         if (grow)
           os << ")" << endl
@@ -1570,7 +1633,8 @@ namespace relational
         else
           os << "composite_value_traits< ";
 
-        os << class_fq_name (c) << ", id_" << db << " >::init (i, o, sk)";
+        os << class_fq_name (c) << ", id_" << db << " >::init (i, o, sk" <<
+          (versioned (c) ? ", svm" : "") << ")";
 
         if (generate_grow)
           os << ")" << endl
@@ -1661,7 +1725,7 @@ namespace relational
         if (ignore_implicit_discriminator_ && discriminator (mi.m))
           return false;
 
-        bool comp (composite (mi.t));
+        semantics::class_* comp (composite (mi.t));
 
         if (!member_override_.empty ())
         {
@@ -1676,8 +1740,29 @@ namespace relational
             return false;
 
           os << "// " << mi.m.name () << endl
-             << "//" << endl
-             << "{";
+             << "//" << endl;
+
+          // If the member is soft- added or deleted, check the version.
+          //
+          unsigned long long av (added (mi.m));
+          unsigned long long dv (deleted (mi.m));
+          if (av != 0 || dv != 0)
+          {
+            os << "if (";
+
+            if (av != 0)
+              os << "svm >= schema_version_migration (" << av << "ULL, true)";
+
+            if (av != 0 && dv != 0)
+              os << " &&" << endl;
+
+            if (dv != 0)
+              os << "svm <= schema_version_migration (" << dv << "ULL, true)";
+
+            os << ")";
+          }
+
+          os << "{";
 
           // Get the member using the accessor expression.
           //
@@ -1686,7 +1771,7 @@ namespace relational
           // Make sure this kind of member can be modified with this
           // kind of accessor (database-specific, e.g., streaming).
           //
-          if (!comp)
+          if (comp == 0)
             check_modifier (mi, ma);
 
           // If this is not a synthesized expression, then output
@@ -1734,7 +1819,7 @@ namespace relational
         // simple values this is taken care of by the value_traits
         // specializations.
         //
-        if (mi.wrapper != 0 && comp)
+        if (mi.wrapper != 0 && comp != 0)
         {
           // The wrapper type, not the wrapped type.
           //
@@ -1748,7 +1833,8 @@ namespace relational
           {
             os << "if (composite_value_traits< " << mi.fq_type () <<
               ", id_" << db << " >::get_null (" << endl
-               << "i." << mi.var << "value))" << endl
+               << "i." << mi.var << "value" <<
+              (versioned (*comp) ? ", svm" : "") << "))" << endl
                << "wrapper_traits< " << wt << " >::set_null (" << member + ");"
                << "else" << endl;
           }
@@ -1770,10 +1856,11 @@ namespace relational
 
           os << "if (";
 
-          if (comp)
+          if (comp != 0)
             os << "composite_value_traits< " << type << ", id_" << db <<
               " >::get_null (" << endl
-               << "i." << mi.var << "value)";
+               << "i." << mi.var << "value" <<
+              (versioned (*comp) ? ", svm" : "") << ")";
           else
             get_null (mi);
 
@@ -1795,7 +1882,7 @@ namespace relational
         else
           type = mi.fq_type ();
 
-        if (comp)
+        if (comp != 0)
           traits = "composite_value_traits< " + type + ", id_" +
             db.string () + " >";
         else
@@ -1883,7 +1970,13 @@ namespace relational
         os << traits << "::init (" << endl
            << member << "," << endl
            << "i." << mi.var << "value," << endl
-           << "db);"
+           << "db";
+
+        if (versioned (*composite (mi.t)))
+          os << "," << endl
+             << "svm";
+
+        os << ");"
            << endl;
       }
 
@@ -1918,7 +2011,8 @@ namespace relational
         else
           os << "composite_value_traits< ";
 
-        os << class_fq_name (c) << ", id_" << db << " >::init (o, i, db);"
+        os << class_fq_name (c) << ", id_" << db << " >::init (o, i, db" <<
+          (versioned (c) ? ", svm" : "") << ");"
            << endl;
       }
     };
@@ -2083,7 +2177,7 @@ namespace relational
         //
         if (!reuse_abst)
         {
-          bool versioned (force_versioned);
+          bool versioned (context::versioned (m));
           string sep (versioned ? "\n" : " ");
 
           semantics::type& idt (container_idt (m));
@@ -2625,7 +2719,7 @@ namespace relational
              << "std::size_t n (0);"
              << endl;
 
-          os << "// key" << endl
+          os << "// value" << endl
              << "//" << endl;
           instance<bind_member> bm ("value_", "d", vt, "value_type", "value");
           bm->traverse (m);
@@ -3682,7 +3776,7 @@ namespace relational
           if (av != 0)
             os << "svm >= schema_version_migration (" << av << "ULL, true)";
 
-          if (av != 0 || dv != 0)
+          if (av != 0 && dv != 0)
             os << " &&" << endl;
 
           if (dv != 0)
@@ -5091,6 +5185,8 @@ namespace relational
       virtual void
       traverse_composite (type& c)
       {
+        bool versioned (context::versioned (c));
+
         string const& type (class_fq_name (c));
         string traits ("access::composite_value_traits< " + type + ", id_" +
                        db.string () + " >");
@@ -5111,11 +5207,22 @@ namespace relational
         if (generate_grow)
         {
           os << "bool " << traits << "::" << endl
-             << "grow (image_type& i, " << truncated_vector << " t)"
+             << "grow (image_type& i," << endl
+             << truncated_vector << " t";
+
+          if (versioned)
+            os << "," << endl
+               << "const schema_version_migration& svm";
+
+          os << ")"
              << "{"
              << "ODB_POTENTIALLY_UNUSED (i);"
-             << "ODB_POTENTIALLY_UNUSED (t);"
-             << endl
+             << "ODB_POTENTIALLY_UNUSED (t);";
+
+          if (versioned)
+            os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+          os << endl
              << "bool grew (false);"
              << endl;
 
@@ -5130,13 +5237,24 @@ namespace relational
         // bind (image_type)
         //
         os << "void " << traits << "::" << endl
-           << "bind (" << bind_vector << " b, image_type& i, " <<
-          db << "::statement_kind sk)"
+           << "bind (" << bind_vector << " b," << endl
+           << "image_type& i," << endl
+           << db << "::statement_kind sk";
+
+        if (versioned)
+          os << "," << endl
+             << "const schema_version_migration& svm";
+
+        os << ")"
            << "{"
            << "ODB_POTENTIALLY_UNUSED (b);"
            << "ODB_POTENTIALLY_UNUSED (i);"
-           << "ODB_POTENTIALLY_UNUSED (sk);"
-           << endl
+           << "ODB_POTENTIALLY_UNUSED (sk);";
+
+        if (versioned)
+          os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+        os << endl
            << "using namespace " << db << ";"
            << endl;
 
@@ -5156,13 +5274,24 @@ namespace relational
         // init (image, value)
         //
         os << (generate_grow ? "bool " : "void ") << traits << "::" << endl
-           << "init (image_type& i, const value_type& o, " <<
-          db << "::statement_kind sk)"
+           << "init (image_type& i," << endl
+           << "const value_type& o," << endl
+           << db << "::statement_kind sk";
+
+        if (versioned)
+          os << "," << endl
+             << "const schema_version_migration& svm";
+
+        os << ")"
            << "{"
            << "ODB_POTENTIALLY_UNUSED (i);"
            << "ODB_POTENTIALLY_UNUSED (o);"
-           << "ODB_POTENTIALLY_UNUSED (sk);"
-           << endl
+           << "ODB_POTENTIALLY_UNUSED (sk);";
+
+        if (versioned)
+          os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+        os << endl
            << "using namespace " << db << ";"
            << endl;
 
@@ -5185,12 +5314,24 @@ namespace relational
         // init (value, image)
         //
         os << "void " << traits << "::" << endl
-           << "init (value_type& o, const image_type&  i, database* db)"
+           << "init (value_type& o," << endl
+           << "const image_type&  i," << endl
+           << "database* db";
+
+        if (versioned)
+          os << "," << endl
+             << "const schema_version_migration& svm";
+
+        os << ")"
            << "{"
            << "ODB_POTENTIALLY_UNUSED (o);"
            << "ODB_POTENTIALLY_UNUSED (i);"
-           << "ODB_POTENTIALLY_UNUSED (db);"
-           << endl;
+           << "ODB_POTENTIALLY_UNUSED (db);";
+
+        if (versioned)
+          os << "ODB_POTENTIALLY_UNUSED (svm);";
+
+        os << endl;
 
         inherits (c, init_value_base_inherits_);
         names (c, init_value_member_names_);