Add support for mapping char[N] to CHAR/VARCHAR database types

Also improve query support for arrays (decaying).

4 files changed, 473 insertions, 233 deletions

diff --git a/odb/oracle/query.hxx b/odb/oracle/query.hxx
index cf35559..f3c94f4 100644
--- a/odb/oracle/query.hxx
+++ b/odb/oracle/query.hxx
@@ -39,37 +39,95 @@ namespace odb
     // bytes per character).
     //
     template <typename T>
-    class val_bind
+    struct val_bind
     {
-    public:
+      typedef const T& type;
+
       explicit
-      val_bind (const T& v, unsigned short p = 0xFFF, short s = 0xFFF)
-          : val (v), prec (p), scale (s)
-      {
-      }
+      val_bind (type v, unsigned short p = 0xFFF, short s = 0xFFF)
+          : val (v), prec (p), scale (s) {}
 
-      const T& val;
+      type val;
+
+      unsigned short prec;
+      short scale;
+    };
+
+    template <typename T, std::size_t N>
+    struct val_bind<T[N]>
+    {
+      typedef const T* type;
+
+      explicit
+      val_bind (type v, unsigned short p = 0xFFF, short s = 0xFFF)
+          : val (v), prec (p), scale (s) {}
+
+      type val;
 
       unsigned short prec;
       short scale;
     };
 
     template <typename T>
-    class ref_bind
+    struct ref_bind
     {
-    public:
+      typedef const T& type;
+
       explicit
-      ref_bind (const T& r, unsigned short p = 0xFFF, short s = 0xFFF)
-          : ref (r), prec (p), scale (s)
-      {
-      }
+      ref_bind (type r, unsigned short p = 0xFFF, short s = 0xFFF)
+          : ref (r), prec (p), scale (s) {}
+
+      const void*
+      ptr () const {return &ref;}
+
+      type ref;
+
+      unsigned short prec;
+      short scale;
+    };
+
+    template <typename T, std::size_t N>
+    struct ref_bind<T[N]>
+    {
+      typedef const T* type;
 
-      const T& ref;
+      explicit
+      ref_bind (type r, unsigned short p = 0xFFF, short s = 0xFFF)
+          : ref (r), prec (p), scale (s) {}
+
+      // Allow implicit conversion from decayed ref_bind's.
+      //
+      ref_bind (ref_bind<T*> r): ref (r.ref), prec (r.prec), scale (r.scale) {}
+      ref_bind (ref_bind<const T*> r)
+          : ref (r.ref), prec (r.prec), scale (r.scale) {}
+
+      const void*
+      ptr () const {return ref;}
+
+      type ref;
 
       unsigned short prec;
       short scale;
     };
 
+    template <typename T, database_type_id ID>
+    struct val_bind_typed: val_bind<T>
+    {
+      explicit
+      val_bind_typed (typename val_bind<T>::type v,
+                      unsigned short p = 0xFFF,
+                      short s = 0xFFF): val_bind<T> (v, p, s) {}
+    };
+
+    template <typename T, database_type_id ID>
+    struct ref_bind_typed: ref_bind<T>
+    {
+      explicit
+      ref_bind_typed (typename ref_bind<T>::type r,
+                      unsigned short p = 0xFFF,
+                      short s = 0xFFF): ref_bind<T> (r, p, s) {}
+    };
+
     struct LIBODB_ORACLE_EXPORT query_param: details::shared_base
     {
       typedef oracle::bind bind_type;
@@ -165,8 +223,15 @@ namespace odb
       query_base (val_bind<T> v)
         : binding_ (0, 0)
       {
-        append<T, type_traits<T>::db_type_id> (
-          v, details::conversion<T>::to ());
+        *this += v;
+      }
+
+      template <typename T, database_type_id ID>
+      explicit
+      query_base (val_bind_typed<T, ID> v)
+        : binding_ (0, 0)
+      {
+        *this += v;
       }
 
       template <typename T>
@@ -174,8 +239,15 @@ namespace odb
       query_base (ref_bind<T> r)
         : binding_ (0, 0)
       {
-        append<T, type_traits<T>::db_type_id> (
-          r, details::conversion<T>::to ());
+        *this += r;
+      }
+
+      template <typename T, database_type_id ID>
+      explicit
+      query_base (ref_bind_typed<T, ID> r)
+        : binding_ (0, 0)
+      {
+        *this += r;
       }
 
       template <database_type_id ID>
@@ -236,6 +308,13 @@ namespace odb
         return val_bind<T> (x, prec, scale);
       }
 
+      template <database_type_id ID, typename T>
+      static val_bind_typed<T, ID>
+      _val (const T& x, unsigned short prec = 0xFFF, short scale = 0xFFF)
+      {
+        return val_bind_typed<T, ID> (x, prec, scale);
+      }
+
       template <typename T>
       static ref_bind<T>
       _ref (const T& x, unsigned short prec = 0xFFF, short scale = 0xFFF)
@@ -243,6 +322,13 @@ namespace odb
         return ref_bind<T> (x, prec, scale);
       }
 
+      template <database_type_id ID, typename T>
+      static ref_bind_typed<T, ID>
+      _ref (const T& x, unsigned short prec = 0xFFF, short scale = 0xFFF)
+      {
+        return ref_bind_typed<T, ID> (x, prec, scale);
+      }
+
     public:
       query_base&
       operator+= (const query_base&);
@@ -263,6 +349,17 @@ namespace odb
         return *this;
       }
 
+      template <typename T, database_type_id ID>
+      query_base&
+      operator+= (val_bind_typed<T, ID> v)
+      {
+        // We are not using default type_traits so no default conversion
+        // either.
+        //
+        append<T, ID> (v, 0);
+        return *this;
+      }
+
       template <typename T>
       query_base&
       operator+= (ref_bind<T> r)
@@ -272,6 +369,17 @@ namespace odb
         return *this;
       }
 
+      template <typename T, database_type_id ID>
+      query_base&
+      operator+= (ref_bind_typed<T, ID> r)
+      {
+        // We are not using default type_traits so no default conversion
+        // either.
+        //
+        append<T, ID> (r, 0);
+        return *this;
+      }
+
       // Implementation details.
       //
     public:
@@ -333,16 +441,26 @@ namespace odb
 
     template <typename T>
     inline query_base
-    operator+ (const query_base& q, ref_bind<T> b)
+    operator+ (val_bind<T> b, const query_base& q)
+    {
+      query_base r;
+      r += b;
+      r += q;
+      return r;
+    }
+
+    template <typename T, database_type_id ID>
+    inline query_base
+    operator+ (const query_base& q, val_bind_typed<T, ID> b)
     {
       query_base r (q);
       r += b;
       return r;
     }
 
-    template <typename T>
+    template <typename T, database_type_id ID>
     inline query_base
-    operator+ (val_bind<T> b, const query_base& q)
+    operator+ (val_bind_typed<T, ID> b, const query_base& q)
     {
       query_base r;
       r += b;
@@ -352,6 +470,15 @@ namespace odb
 
     template <typename T>
     inline query_base
+    operator+ (const query_base& q, ref_bind<T> b)
+    {
+      query_base r (q);
+      r += b;
+      return r;
+    }
+
+    template <typename T>
+    inline query_base
     operator+ (ref_bind<T> b, const query_base& q)
     {
       query_base r;
@@ -360,6 +487,25 @@ namespace odb
       return r;
     }
 
+    template <typename T, database_type_id ID>
+    inline query_base
+    operator+ (const query_base& q, ref_bind_typed<T, ID> b)
+    {
+      query_base r (q);
+      r += b;
+      return r;
+    }
+
+    template <typename T, database_type_id ID>
+    inline query_base
+    operator+ (ref_bind_typed<T, ID> b, const query_base& q)
+    {
+      query_base r;
+      r += b;
+      r += q;
+      return r;
+    }
+
     inline query_base
     operator+ (const query_base& q, const std::string& s)
     {
@@ -387,16 +533,26 @@ namespace odb
 
     template <typename T>
     inline query_base
-    operator+ (const std::string& s, ref_bind<T> b)
+    operator+ (val_bind<T> b, const std::string& s)
+    {
+      query_base r;
+      r += b;
+      r += s;
+      return r;
+    }
+
+    template <typename T, database_type_id ID>
+    inline query_base
+    operator+ (const std::string& s, val_bind_typed<T, ID> b)
     {
       query_base r (s);
       r += b;
       return r;
     }
 
-    template <typename T>
+    template <typename T, database_type_id ID>
     inline query_base
-    operator+ (val_bind<T> b, const std::string& s)
+    operator+ (val_bind_typed<T, ID> b, const std::string& s)
     {
       query_base r;
       r += b;
@@ -406,6 +562,15 @@ namespace odb
 
     template <typename T>
     inline query_base
+    operator+ (const std::string& s, ref_bind<T> b)
+    {
+      query_base r (s);
+      r += b;
+      return r;
+    }
+
+    template <typename T>
+    inline query_base
     operator+ (ref_bind<T> b, const std::string& s)
     {
       query_base r;
@@ -414,6 +579,25 @@ namespace odb
       return r;
     }
 
+    template <typename T, database_type_id ID>
+    inline query_base
+    operator+ (const std::string& s, ref_bind_typed<T, ID> b)
+    {
+      query_base r (s);
+      r += b;
+      return r;
+    }
+
+    template <typename T, database_type_id ID>
+    inline query_base
+    operator+ (ref_bind_typed<T, ID> b, const std::string& s)
+    {
+      query_base r;
+      r += b;
+      r += s;
+      return r;
+    }
+
     LIBODB_ORACLE_EXPORT query_base
     operator&& (const query_base& x, const query_base& y);
 
@@ -481,23 +665,11 @@ namespace odb
       short scale_;
     };
 
-    template <typename T, typename T2>
-    class copy_bind: public val_bind<T>
-    {
-    public:
-      explicit
-      copy_bind (const T2& v): val_bind<T> (val), val (v) {}
-
-      const T val;
-    };
-
-    template <typename T>
-    const T&
-    type_instance ();
-
     template <typename T, database_type_id ID>
     struct query_column: query_column_base
     {
+      typedef typename decay_traits<T>::type decayed_type;
+
       // Note that we keep shalow copies of the table, column, and conversion
       // expression. The latter can be NULL.
       //
@@ -540,16 +712,17 @@ namespace odb
       //
     public:
       query_base
-      in (const T&, const T&) const;
+      in (decayed_type, decayed_type) const;
 
       query_base
-      in (const T&, const T&, const T&) const;
+      in (decayed_type, decayed_type, decayed_type) const;
 
       query_base
-      in (const T&, const T&, const T&, const T&) const;
+      in (decayed_type, decayed_type, decayed_type, decayed_type) const;
 
       query_base
-      in (const T&, const T&, const T&, const T&, const T&) const;
+      in (decayed_type, decayed_type, decayed_type, decayed_type,
+          decayed_type) const;
 
       template <typename I>
       query_base
@@ -559,7 +732,7 @@ namespace odb
       //
     public:
       query_base
-      equal (const T& v) const
+      equal (decayed_type v) const
       {
         return equal (val_bind<T> (v));
       }
@@ -580,8 +753,7 @@ namespace odb
       query_base
       equal (val_bind<T2> v) const
       {
-        copy_bind<T, T2> c (v.val);
-        return equal (c);
+        return equal (val_bind<T> (decayed_type (v.val)));
       }
 
       query_base
@@ -597,13 +769,13 @@ namespace odb
       }
 
       friend query_base
-      operator== (const query_column& c, const T& v)
+      operator== (const query_column& c, decayed_type v)
       {
         return c.equal (v);
       }
 
       friend query_base
-      operator== (const T& v, const query_column& c)
+      operator== (decayed_type v, const query_column& c)
       {
         return c.equal (v);
       }
@@ -650,7 +822,7 @@ namespace odb
       //
     public:
       query_base
-      unequal (const T& v) const
+      unequal (decayed_type v) const
       {
         return unequal (val_bind<T> (v));
       }
@@ -671,8 +843,7 @@ namespace odb
       query_base
       unequal (val_bind<T2> v) const
       {
-        copy_bind<T, T2> c (v.val);
-        return unequal (c);
+        return unequal (val_bind<T> (decayed_type (v.val)));
       }
 
       query_base
@@ -688,13 +859,13 @@ namespace odb
       }
 
       friend query_base
-      operator!= (const query_column& c, const T& v)
+      operator!= (const query_column& c, decayed_type v)
       {
         return c.unequal (v);
       }
 
       friend query_base
-      operator!= (const T& v, const query_column& c)
+      operator!= (decayed_type v, const query_column& c)
       {
         return c.unequal (v);
       }
@@ -741,7 +912,7 @@ namespace odb
       //
     public:
       query_base
-      less (const T& v) const
+      less (decayed_type v) const
       {
         return less (val_bind<T> (v));
       }
@@ -762,8 +933,7 @@ namespace odb
       query_base
       less (val_bind<T2> v) const
       {
-        copy_bind<T, T2> c (v.val);
-        return less (c);
+        return less (val_bind<T> (decayed_type (v.val)));
       }
 
       query_base
@@ -779,13 +949,13 @@ namespace odb
       }
 
       friend query_base
-      operator< (const query_column& c, const T& v)
+      operator< (const query_column& c, decayed_type v)
       {
         return c.less (v);
       }
 
       friend query_base
-      operator< (const T& v, const query_column& c)
+      operator< (decayed_type v, const query_column& c)
       {
         return c.greater (v);
       }
@@ -832,7 +1002,7 @@ namespace odb
       //
     public:
       query_base
-      greater (const T& v) const
+      greater (decayed_type v) const
       {
         return greater (val_bind<T> (v));
       }
@@ -853,8 +1023,7 @@ namespace odb
       query_base
       greater (val_bind<T2> v) const
       {
-        copy_bind<T, T2> c (v.val);
-        return greater (c);
+        return greater (val_bind<T> (decayed_type (v.val)));
       }
 
       query_base
@@ -870,13 +1039,13 @@ namespace odb
       }
 
       friend query_base
-      operator> (const query_column& c, const T& v)
+      operator> (const query_column& c, decayed_type v)
       {
         return c.greater (v);
       }
 
       friend query_base
-      operator> (const T& v, const query_column& c)
+      operator> (decayed_type v, const query_column& c)
       {
         return c.less (v);
       }
@@ -923,7 +1092,7 @@ namespace odb
       //
     public:
       query_base
-      less_equal (const T& v) const
+      less_equal (decayed_type v) const
       {
         return less_equal (val_bind<T> (v));
       }
@@ -944,8 +1113,7 @@ namespace odb
       query_base
       less_equal (val_bind<T2> v) const
       {
-        copy_bind<T, T2> c (v.val);
-        return less_equal (c);
+        return less_equal (val_bind<T> (decayed_type (v.val)));
       }
 
       query_base
@@ -961,13 +1129,13 @@ namespace odb
       }
 
       friend query_base
-      operator<= (const query_column& c, const T& v)
+      operator<= (const query_column& c, decayed_type v)
       {
         return c.less_equal (v);
       }
 
       friend query_base
-      operator<= (const T& v, const query_column& c)
+      operator<= (decayed_type v, const query_column& c)
       {
         return c.greater_equal (v);
       }
@@ -1014,7 +1182,7 @@ namespace odb
       //
     public:
       query_base
-      greater_equal (const T& v) const
+      greater_equal (decayed_type v) const
       {
         return greater_equal (val_bind<T> (v));
       }
@@ -1035,8 +1203,7 @@ namespace odb
       query_base
       greater_equal (val_bind<T2> v) const
       {
-        copy_bind<T, T2> c (v.val);
-        return greater_equal (c);
+        return greater_equal (val_bind<T> (decayed_type (v.val)));
       }
 
       query_base
@@ -1052,13 +1219,13 @@ namespace odb
       }
 
       friend query_base
-      operator>= (const query_column& c, const T& v)
+      operator>= (const query_column& c, decayed_type v)
       {
         return c.greater_equal (v);
       }
 
       friend query_base
-      operator>= (const T& v, const query_column& c)
+      operator>= (decayed_type v, const query_column& c)
       {
         return c.less_equal (v);
       }
@@ -1110,7 +1277,8 @@ namespace odb
       {
         // We can compare columns only if we can compare their C++ types.
         //
-        (void) (sizeof (type_instance<T> () == type_instance<T2> ()));
+        (void) (sizeof (decay_traits<T>::instance () ==
+                        decay_traits<T2>::instance ()));
 
         query_base q (table_, column_);
         q += "=";
@@ -1124,7 +1292,8 @@ namespace odb
       {
         // We can compare columns only if we can compare their C++ types.
         //
-        (void) (sizeof (type_instance<T> () != type_instance<T2> ()));
+        (void) (sizeof (decay_traits<T>::instance () !=
+                        decay_traits<T2>::instance ()));
 
         query_base q (table_, column_);
         q += "!=";
@@ -1138,7 +1307,8 @@ namespace odb
       {
         // We can compare columns only if we can compare their C++ types.
         //
-        (void) (sizeof (type_instance<T> () < type_instance<T2> ()));
+        (void) (sizeof (decay_traits<T>::instance () <
+                        decay_traits<T2>::instance ()));
 
         query_base q (table_, column_);
         q += "<";
@@ -1152,7 +1322,8 @@ namespace odb
       {
         // We can compare columns only if we can compare their C++ types.
         //
-        (void) (sizeof (type_instance<T> () > type_instance<T2> ()));
+        (void) (sizeof (decay_traits<T>::instance () >
+                        decay_traits<T2>::instance ()));
 
         query_base q (table_, column_);
         q += ">";
@@ -1166,7 +1337,8 @@ namespace odb
       {
         // We can compare columns only if we can compare their C++ types.
         //
-        (void) (sizeof (type_instance<T> () <= type_instance<T2> ()));
+        (void) (sizeof (decay_traits<T>::instance () <=
+                        decay_traits<T2>::instance ()));
 
         query_base q (table_, column_);
         q += "<=";
@@ -1180,7 +1352,8 @@ namespace odb
       {
         // We can compare columns only if we can compare their C++ types.
         //
-        (void) (sizeof (type_instance<T> () >= type_instance<T2> ()));
+        (void) (sizeof (decay_traits<T>::instance () >=
+                        decay_traits<T2>::instance ()));
 
         query_base q (table_, column_);
         q += ">=";
@@ -1317,7 +1490,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_int32>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1338,7 +1511,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_int32>::set_image (image_, is_null, v);
@@ -1353,7 +1526,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_int64>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1374,7 +1547,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_int64>::set_image (image_, is_null, v);
@@ -1389,7 +1562,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_big_int>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1410,7 +1583,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         std::size_t size (0);
@@ -1428,7 +1601,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_float>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1449,7 +1622,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_float>::set_image (image_, is_null, v);
@@ -1464,7 +1637,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_double>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1485,7 +1658,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_double>::set_image (image_, is_null, v);
@@ -1500,7 +1673,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_big_float>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1521,7 +1694,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         std::size_t size (0);
@@ -1539,7 +1712,7 @@ namespace odb
     template <typename T>
     struct query_param_impl<T, id_date>: query_param
     {
-      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (ref_bind<T> r) : query_param (r.ptr ()) {}
       query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
 
       virtual bool
@@ -1560,7 +1733,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_date>::set_image (image_, is_null, v);
@@ -1576,7 +1749,7 @@ namespace odb
     struct query_param_impl<T, id_timestamp>: query_param
     {
       query_param_impl (ref_bind<T> r)
-          : query_param (&r.ref),
+          : query_param (r.ptr ()),
             image_ (descriptor_cache) // Cache, don't free.
       {
       }
@@ -1606,7 +1779,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_timestamp>::set_image (image_, is_null, v);
@@ -1622,7 +1795,7 @@ namespace odb
     struct query_param_impl<T, id_interval_ym>: query_param
     {
       query_param_impl (ref_bind<T> r)
-          : query_param (&r.ref),
+          : query_param (r.ptr ()),
             image_ (descriptor_cache) // Cache, don't free.
       {
       }
@@ -1652,7 +1825,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_interval_ym>::set_image (image_, is_null, v);
@@ -1668,7 +1841,7 @@ namespace odb
     struct query_param_impl<T, id_interval_ds>: query_param
     {
       query_param_impl (ref_bind<T> r)
-          : query_param (&r.ref),
+          : query_param (r.ptr ()),
             image_ (descriptor_cache) // Cache, don't free.
       {
       }
@@ -1699,7 +1872,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         value_traits<T, id_interval_ds>::set_image (image_, is_null, v);
@@ -1715,7 +1888,7 @@ namespace odb
     struct query_param_impl<T, id_string>: query_param
     {
       query_param_impl (ref_bind<T> r)
-          : query_param (&r.ref),
+          : query_param (r.ptr ()),
             // Default to max (4000).
             buf_ (r.prec != 0xFFF ? r.prec : 4000)
       {
@@ -1748,7 +1921,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         std::size_t size (0);
@@ -1768,7 +1941,7 @@ namespace odb
     struct query_param_impl<T, id_nstring>: query_param
     {
       query_param_impl (ref_bind<T> r)
-          : query_param (&r.ref),
+          : query_param (r.ptr ()),
             // Default to max (4000).
             buf_ (r.prec != 0xFFF ? r.prec : 4000)
       {
@@ -1801,7 +1974,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         std::size_t size (0);
@@ -1821,7 +1994,7 @@ namespace odb
     struct query_param_impl<T, id_raw>: query_param
     {
       query_param_impl (ref_bind<T> r)
-          : query_param (&r.ref),
+          : query_param (r.ptr ()),
             // Default to max (2000).
             buf_ (r.prec != 0xFFF ? r.prec : 2000)
       {
@@ -1854,7 +2027,7 @@ namespace odb
 
     private:
       void
-      init (const T& v)
+      init (typename decay_traits<T>::type v)
       {
         bool is_null (false); // Can't be NULL.
         std::size_t size (0);
diff --git a/odb/oracle/query.txx b/odb/oracle/query.txx
index 5921efe..879072b 100644
--- a/odb/oracle/query.txx
+++ b/odb/oracle/query.txx
@@ -27,7 +27,7 @@ namespace odb
     //
     template <typename T, database_type_id ID>
     query_base query_column<T, ID>::
-    in (const T& v1, const T& v2) const
+    in (decayed_type v1, decayed_type v2) const
     {
       query_base q (table_, column_);
       q += "IN (";
@@ -40,7 +40,7 @@ namespace odb
 
     template <typename T, database_type_id ID>
     query_base query_column<T, ID>::
-    in (const T& v1, const T& v2, const T& v3) const
+    in (decayed_type v1, decayed_type v2, decayed_type v3) const
     {
       query_base q (table_, column_);
       q += "IN (";
@@ -55,7 +55,8 @@ namespace odb
 
     template <typename T, database_type_id ID>
     query_base query_column<T, ID>::
-    in (const T& v1, const T& v2, const T& v3, const T& v4) const
+    in (decayed_type v1, decayed_type v2, decayed_type v3,
+        decayed_type v4) const
     {
       query_base q (table_, column_);
       q += "IN (";
@@ -72,7 +73,8 @@ namespace odb
 
     template <typename T, database_type_id ID>
     query_base query_column<T, ID>::
-    in (const T& v1, const T& v2, const T& v3, const T& v4, const T& v5) const
+    in (decayed_type v1, decayed_type v2, decayed_type v3, decayed_type v4,
+        decayed_type v5) const
     {
       query_base q (table_, column_);
       q += "IN (";
diff --git a/odb/oracle/traits.cxx b/odb/oracle/traits.cxx
index 6927f65..5ab0d1e 100644
--- a/odb/oracle/traits.cxx
+++ b/odb/oracle/traits.cxx
@@ -11,9 +11,54 @@ namespace odb
   namespace oracle
   {
     //
-    // string_lob_value_traits
+    // c_array_value_traits_base
     //
+    void c_array_value_traits_base::
+    set_value (char* const& v,
+               const char* b,
+               size_t n,
+               bool is_null,
+               size_t N)
+    {
+      if (!is_null)
+      {
+        n = n < N ? n : N;
+
+        if (n != 0)
+          memcpy (v, b, n);
+      }
+      else
+        n = 0;
+
+      if (n != N) // Append '\0' if there is space.
+        v[n] = '\0';
+    }
+
+    void c_array_value_traits_base::
+    set_image (char* b,
+               size_t c,
+               size_t& n,
+               bool& is_null,
+               const char* v,
+               size_t N)
+    {
+      is_null = false;
 
+      // Figure out the length. We cannot use strlen since it may
+      // not be 0-terminated (strnlen is not standard).
+      //
+      for (n = 0; n != N && v[n] != '\0'; ++n);
+
+      if (n > c)
+        n = c;
+
+      if (n != 0)
+        memcpy (b, v, n);
+    }
+
+    //
+    // string_lob_value_traits
+    //
     bool string_lob_value_traits::
     result_callback (void* c, ub4*, void* b, ub4 s, chunk_position p)
     {
@@ -58,31 +103,8 @@ namespace odb
     }
 
     //
-    // c_string_lob_value_traits
-    //
-
-    bool c_string_lob_value_traits::
-    param_callback (const void* c,
-                    ub4*,
-                    const void** b,
-                    ub4* s,
-                    chunk_position* p,
-                    void*,
-                    ub4)
-    {
-      const char* v (static_cast<const char*> (c));
-
-      *p = chunk_one;
-      *s = static_cast<ub4> (strlen (v));
-      *b = v;
-
-      return true;
-    }
-
-    //
     // default_value_traits<std::vector<char>, id_blob>
     //
-
     bool default_value_traits<std::vector<char>, id_blob>::
     result_callback (void* c, ub4*, void* b, ub4 s, chunk_position p)
     {
@@ -131,7 +153,6 @@ namespace odb
     //
     // default_value_traits<std::vector<unsigned char>, id_blob>
     //
-
     bool default_value_traits<std::vector<unsigned char>, id_blob>::
     result_callback (void* c, ub4*, void* b, ub4 s, chunk_position p)
     {
diff --git a/odb/oracle/traits.hxx b/odb/oracle/traits.hxx
index 2cbce04..13bb1dc 100644
--- a/odb/oracle/traits.hxx
+++ b/odb/oracle/traits.hxx
@@ -546,7 +546,7 @@ namespace odb
     {
     };
 
-    // const char* specialization.
+    // char*/const char* specialization.
     //
     // Specialization for const char* which only supports initialization
     // of an image from the value but not the other way around. This way
@@ -577,45 +577,151 @@ namespace odb
     };
 
     template <>
+    struct LIBODB_ORACLE_EXPORT default_value_traits<char*, id_string>:
+      c_string_value_traits {};
+
+    template <>
+    struct LIBODB_ORACLE_EXPORT default_value_traits<char*, id_nstring>:
+      c_string_value_traits {};
+
+    template <>
     struct LIBODB_ORACLE_EXPORT default_value_traits<const char*, id_string>:
-      c_string_value_traits
-    {
-      typedef const char* query_type;
-    };
+      c_string_value_traits {};
 
     template <>
     struct LIBODB_ORACLE_EXPORT default_value_traits<const char*, id_nstring>:
-      c_string_value_traits
+      c_string_value_traits {};
+
+    // char[N] specializations.
+    //
+    struct LIBODB_ORACLE_EXPORT c_array_value_traits_base
     {
-      typedef const char* query_type;
+      static void
+      set_value (char* const& v,
+                 const char* b,
+                 std::size_t n,
+                 bool is_null,
+                 std::size_t N);
+
+      static void
+      set_image (char* b,
+                 std::size_t c,
+                 std::size_t& n,
+                 bool& is_null,
+                 const char* v,
+                 std::size_t N);
     };
 
     template <std::size_t N>
-    struct default_value_traits<char[N], id_string>: c_string_value_traits
+    struct c_array_value_traits
     {
+      typedef char* value_type;
       typedef char query_type[N];
+      typedef details::buffer image_type;
+
+      static void
+      set_value (char* const& v,
+                 const char* b,
+                 std::size_t n,
+                 bool is_null)
+      {
+        c_array_value_traits_base::set_value (v, b, n, is_null, N);
+      }
+
+      static void
+      set_image (char* b,
+                 std::size_t c,
+                 std::size_t& n,
+                 bool& is_null,
+                 const char* v)
+      {
+        c_array_value_traits_base::set_image (b, c, n, is_null, v, N);
+      }
     };
 
     template <std::size_t N>
-    struct default_value_traits<const char[N], id_string>:
-      c_string_value_traits
-    {
-      typedef const char query_type[N];
-    };
+    struct default_value_traits<char[N], id_string>:
+      c_array_value_traits<N> {};
 
     template <std::size_t N>
-    struct default_value_traits<char[N], id_nstring>: c_string_value_traits
+    struct default_value_traits<char[N], id_nstring>:
+      c_array_value_traits<N> {};
+
+    // std::array<char, N> (string) specialization.
+    //
+#ifdef ODB_CXX11
+    template <std::size_t N>
+    struct std_array_value_traits
     {
-      typedef char query_type[N];
+      typedef std::array<char, N> value_type;
+      typedef std::array<char, N> query_type;
+      typedef details::buffer image_type;
+
+      static void
+      set_value (value_type& v,
+                 const char* b,
+                 std::size_t n,
+                 bool is_null)
+      {
+        c_array_value_traits_base::set_value (v.data (), b, n, is_null, N);
+      }
+
+      static void
+      set_image (char* b,
+                 std::size_t c,
+                 std::size_t& n,
+                 bool& is_null,
+                 const value_type& v)
+      {
+        c_array_value_traits_base::set_image (b, c, n, is_null, v.data (), N);
+      }
     };
 
     template <std::size_t N>
-    struct default_value_traits<const char[N], id_nstring>:
-      c_string_value_traits
+    struct default_value_traits<std::array<char, N>, id_string>:
+      std_array_value_traits<N> {};
+
+    template <std::size_t N>
+    struct default_value_traits<std::array<char, N>, id_nstring>:
+      std_array_value_traits<N> {};
+#endif
+
+    // char specialization.
+    //
+    struct LIBODB_ORACLE_EXPORT char_value_traits
     {
-      typedef const char query_type[N];
+      typedef char value_type;
+      typedef char query_type;
+      typedef details::buffer image_type;
+
+      static void
+      set_value (char& v,
+                 const char* b,
+                 std::size_t n,
+                 bool is_null)
+      {
+        c_array_value_traits_base::set_value (&v, b, n, is_null, 1);
+      }
+
+      static void
+      set_image (char* b,
+                 std::size_t c,
+                 std::size_t& n,
+                 bool& is_null,
+                 char v)
+      {
+        c_array_value_traits_base::set_image (b, c, n, is_null, &v, 1);
+      }
     };
 
+    template <>
+    struct LIBODB_ORACLE_EXPORT default_value_traits<char, id_string>:
+      char_value_traits {};
+
+    template <>
+    struct LIBODB_ORACLE_EXPORT default_value_traits<char, id_nstring>:
+      char_value_traits {};
+
     // std::vector<char> (buffer) specialization for RAW.
     //
     template <>
@@ -892,81 +998,6 @@ namespace odb
     {
     };
 
-    // const char* specialization for LOBs.
-    //
-    // Specialization for const char* which only supports initialization
-    // of an image from the value but not the other way around. This way
-    // we can pass such values to the queries.
-    //
-    class LIBODB_ORACLE_EXPORT c_string_lob_value_traits
-    {
-    public:
-      typedef const char* value_type;
-      typedef lob_callback image_type;
-
-      static void
-      set_image (param_callback_type& cb,
-                 const void*& context,
-                 bool& is_null,
-                 const char* v)
-      {
-        is_null = false;
-        cb = &param_callback;
-        context = v;
-      }
-
-      static bool
-      param_callback (const void* context,
-                      ub4* position_context,
-                      const void** buffer,
-                      ub4* size,
-                      chunk_position*,
-                      void* temp_buffer,
-                      ub4 capacity);
-    };
-
-    template <>
-    struct LIBODB_ORACLE_EXPORT default_value_traits<const char*, id_clob>:
-      c_string_lob_value_traits
-    {
-      typedef const char* query_type;
-    };
-
-    template <>
-    struct LIBODB_ORACLE_EXPORT default_value_traits<const char*, id_nclob>:
-      c_string_lob_value_traits
-    {
-      typedef const char* query_type;
-    };
-
-    template <std::size_t N>
-    struct default_value_traits<char[N], id_clob>:
-      c_string_lob_value_traits
-    {
-      typedef char query_type[N];
-    };
-
-    template <std::size_t N>
-    struct default_value_traits<const char[N], id_clob>:
-      c_string_lob_value_traits
-    {
-      typedef const char query_type[N];
-    };
-
-    template <std::size_t N>
-    struct default_value_traits<char[N], id_nclob>:
-      c_string_lob_value_traits
-    {
-      typedef char query_type[N];
-    };
-
-    template <std::size_t N>
-    struct default_value_traits<const char[N], id_nclob>:
-      c_string_lob_value_traits
-    {
-      typedef const char query_type[N];
-    };
-
     // std::vector<char> (buffer) specialization for BLOBs.
     //
     template <>
@@ -1392,6 +1423,12 @@ namespace odb
     };
 
     template <>
+    struct default_type_traits<char*>
+    {
+      static const database_type_id db_type_id = id_string;
+    };
+
+    template <>
     struct default_type_traits<const char*>
     {
       static const database_type_id db_type_id = id_string;
@@ -1403,37 +1440,44 @@ namespace odb
       static const database_type_id db_type_id = id_string;
     };
 
-    template <std::size_t N>
-    struct default_type_traits<const char[N]>
+    template <>
+    struct default_type_traits<char>
     {
       static const database_type_id db_type_id = id_string;
     };
 
-    // Binary types. Assume BLOB.
+    // Binary types. Assume RAW since LOBs cannot be compared in
+    // Oracle and this is only used in queries.
     //
+    template <std::size_t N>
+    struct default_type_traits<unsigned char[N]>
+    {
+      static const database_type_id db_type_id = id_raw;
+    };
+
     template <>
     struct default_type_traits<std::vector<char> >
     {
-      static const database_type_id db_type_id = id_blob;
+      static const database_type_id db_type_id = id_raw;
     };
 
     template <>
     struct default_type_traits<std::vector<unsigned char> >
     {
-      static const database_type_id db_type_id = id_blob;
+      static const database_type_id db_type_id = id_raw;
     };
 
 #ifdef ODB_CXX11
     template <std::size_t N>
     struct default_type_traits<std::array<char, N> >
     {
-      static const database_type_id db_type_id = id_blob;
+      static const database_type_id db_type_id = id_raw;
     };
 
     template <std::size_t N>
     struct default_type_traits<std::array<unsigned char, N> >
     {
-      static const database_type_id db_type_id = id_blob;
+      static const database_type_id db_type_id = id_raw;
     };
 #endif
   }