Add query and result implementation

6 files changed, 2293 insertions, 0 deletions

diff --git a/odb/pgsql/query.cxx b/odb/pgsql/query.cxx
new file mode 100644
index 0000000..ba39564
--- /dev/null
+++ b/odb/pgsql/query.cxx
@@ -0,0 +1,256 @@
+// file      : odb/pgsql/query.cxx
+// author    : Constantin Michael <constantin@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#include <cstddef> // std::size_t
+#include <cstring> // std::memset
+#include <cassert>
+#include <sstream>
+
+#include <odb/pgsql/query.hxx>
+
+using namespace std;
+
+namespace odb
+{
+  namespace pgsql
+  {
+    // query_param
+    //
+    query_param::
+    ~query_param ()
+    {
+    }
+
+    query::
+    query (const query& q)
+        : clause_ (q.clause_),
+          parameters_ (q.parameters_),
+          bind_ (q.bind_),
+          binding_ (0, 0),
+          values_ (q.values_),
+          lengths_ (q.lengths_),
+          formats_ (q.formats_),
+          types_ (q.types_),
+          native_binding_ (0, 0, 0, 0)
+    {
+      // Here and below we want to maintain up to date binding info so
+      // that the call to parameters_binding() below is an immutable
+      // operation, provided the query does not have any by-reference
+      // parameters. This way a by-value-only query can be shared
+      // between multiple threads without the need for synchronization.
+      //
+      if (size_t n = bind_.size ())
+      {
+        binding_.bind = &bind_[0];
+        binding_.count = n;
+        binding_.version++;
+
+        native_binding_.values = &values_[0];
+        native_binding_.lengths = &lengths_[0];
+        native_binding_.formats = &formats_[0];
+        native_binding_.count = n;
+
+        assert (values_.size () == n);
+        assert (lengths_.size () == n);
+        assert (formats_.size () == n);
+        assert (types_.size () == n);
+      }
+    }
+
+    query& query::
+    operator= (const query& q)
+    {
+      if (this != &q)
+      {
+        clause_ = q.clause_;
+        parameters_ = q.parameters_;
+        bind_ = q.bind_;
+
+        size_t n (bind_.size ());
+
+        binding_.count = n;
+        binding_.version++;
+
+        values_ = q.values_;
+        lengths_ = q.lengths_;
+        formats_ = q.formats_;
+        types_ = q.types_;
+
+        native_binding_.count = n;
+
+        assert (values_.size () == n);
+        assert (lengths_.size () == n);
+        assert (formats_.size () == n);
+        assert (types_.size () == n);
+
+        if (n != 0)
+        {
+          binding_.bind = &bind_[0];
+
+          native_binding_.values = &values_[0];
+          native_binding_.lengths = &lengths_[0];
+          native_binding_.formats = &formats_[0];
+        }
+      }
+
+      return *this;
+    }
+
+    query& query::
+    operator+= (const query& q)
+    {
+      size_t n (clause_.size ());
+
+      if (n != 0 && clause_[n - 1] != ' ' &&
+          !q.clause_.empty () && q.clause_[0] != ' ')
+        clause_ += ' ';
+
+      clause_ += q.clause_;
+
+      // Reset parameter indexes.
+      //
+      bool unquoted (true);
+      for (std::size_t i (0), e (clause_.size ()), p(1); i < e; ++i)
+      {
+        // $'s are legal in identifiers in PostgreSQL.
+        //
+        if (clause_[i] == '"')
+          unquoted = !unquoted;
+
+        if (unquoted && clause_[i] == '$')
+        {
+          ostringstream ss;
+          ss << p++;
+          clause_[++i] = ss.str()[0];
+        }
+      }
+
+      n = bind_.size ();
+
+      parameters_.insert (
+        parameters_.end (), q.parameters_.begin (), q.parameters_.end ());
+
+      bind_.insert (
+        bind_.end (), q.bind_.begin (), q.bind_.end ());
+
+      values_.insert (
+        values_.end (), q.values_.begin (), q.values_.end ());
+
+      lengths_.insert (
+        lengths_.end (), q.lengths_.begin (), q.lengths_.end ());
+
+      formats_.insert (
+        formats_.end (), q.formats_.begin (), q.formats_.end ());
+
+      types_.insert (
+        types_.end (), q.types_.begin (), q.types_.end ());
+
+      if (n != bind_.size ())
+      {
+        n = bind_.size ();
+
+        binding_.bind = &bind_[0];
+        binding_.count = n;
+        binding_.version++;
+
+        assert (values_.size () == n);
+        assert (lengths_.size () == n);
+        assert (formats_.size () == n);
+        assert (types_.size () == n);
+
+        native_binding_.values = &values_[0];
+        native_binding_.lengths = &lengths_[0];
+        native_binding_.formats = &formats_[0];
+        native_binding_.count = n;
+      }
+
+      return *this;
+    }
+
+    void query::
+    add (details::shared_ptr<query_param> p)
+    {
+      size_t n (clause_.size ());
+
+      if (n != 0 && clause_[n - 1] != ' ')
+        clause_ += ' ';
+
+      ostringstream ss;
+      ss << parameters_.size () + 1;
+
+      clause_ += '$' + ss.str ();
+
+      parameters_.push_back (p);
+      bind_.push_back (bind ());
+      binding_.bind = &bind_[0];
+      binding_.count = bind_.size ();
+      binding_.version++;
+
+      bind* b (&bind_.back ());
+      memset (b, 0, sizeof (bind));
+      p->bind (b);
+
+      values_.push_back (0);
+      lengths_.push_back (0);
+      formats_.push_back (0);
+      native_binding_.values = &values_[0];
+      native_binding_.lengths = &lengths_[0];
+      native_binding_.formats = &formats_[0];
+
+      types_.push_back (p->oid ());
+
+      // native_binding_.count should always equal binding_.count.
+      // At this point, we know that we have added one element to
+      // each array, so there is no need to check.
+      //
+      native_binding_.count = binding_.count;
+    }
+
+    binding& query::
+    parameters_binding () const
+    {
+      size_t n (parameters_.size ());
+      binding& r (binding_);
+
+      if (n == 0)
+        return r;
+
+      bool inc_ver (false);
+      bind* b (&bind_[0]);
+
+      for (size_t i (0); i < n; ++i)
+      {
+        query_param& p (*parameters_[i]);
+
+        if (p.reference ())
+        {
+          if (p.init ())
+          {
+            p.bind (b + i);
+            inc_ver = true;
+          }
+        }
+      }
+
+      if (inc_ver)
+        r.version++;
+
+      return r;
+    }
+
+    std::string query::
+    clause () const
+    {
+      if (clause_.empty () ||
+          clause_.compare (0, 6, "WHERE ") == 0 ||
+          clause_.compare (0, 9, "ORDER BY ") == 0 ||
+          clause_.compare (0, 9, "GROUP BY ") == 0 ||
+          clause_.compare (0, 7, "HAVING ") == 0)
+        return clause_;
+      else
+        return "WHERE " + clause_;
+    }
+  }
+}
diff --git a/odb/pgsql/query.hxx b/odb/pgsql/query.hxx
new file mode 100644
index 0000000..632fde5
--- /dev/null
+++ b/odb/pgsql/query.hxx
@@ -0,0 +1,1687 @@
+// file      : odb/pgsql/query.hxx
+// author    : Constantin Michael <constantin@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#ifndef ODB_PGSQL_QUERY_HXX
+#define ODB_PGSQL_QUERY_HXX
+
+#include <odb/pre.hxx>
+
+#include <string>
+#include <vector>
+#include <cstddef> // std::size_t
+
+#include <odb/query.hxx>
+
+#include <odb/pgsql/version.hxx>
+#include <odb/pgsql/forward.hxx>
+#include <odb/pgsql/traits.hxx>
+#include <odb/pgsql/binding.hxx>
+#include <odb/pgsql/pgsql-oid.hxx>
+
+#include <odb/details/buffer.hxx>
+#include <odb/details/shared-ptr.hxx>
+
+#include <odb/pgsql/details/export.hxx>
+
+namespace odb
+{
+  namespace pgsql
+  {
+    template <typename T>
+    class val_bind
+    {
+    public:
+      explicit
+      val_bind (const T& v): val (v) {}
+
+      const T& val;
+    };
+
+    template <typename T>
+    class ref_bind
+    {
+    public:
+      explicit
+      ref_bind (const T& r): ref (r) {}
+
+      const T& ref;
+    };
+
+    struct LIBODB_PGSQL_EXPORT query_param: details::shared_base
+    {
+      virtual
+      ~query_param ();
+
+      bool
+      reference () const
+      {
+        return value_ != 0;
+      }
+
+      virtual bool
+      init () = 0;
+
+      virtual void
+      bind (bind*) = 0;
+
+      virtual unsigned int
+      oid () const = 0;
+
+    protected:
+      query_param (const void* value)
+          : value_ (value)
+      {
+      }
+
+    protected:
+      const void* value_;
+    };
+
+    //
+    //
+    template <typename T, database_type_id ID>
+    struct query_column;
+
+    class LIBODB_PGSQL_EXPORT query
+    {
+    public:
+      query ()
+        : binding_ (0, 0), native_binding_ (0, 0, 0, 0)
+      {
+      }
+
+      explicit
+      query (const std::string& q)
+        : clause_ (q), binding_ (0, 0), native_binding_ (0, 0, 0, 0)
+      {
+      }
+
+      template <typename T>
+      explicit
+      query (val_bind<T> v)
+        : binding_ (0, 0), native_binding_ (0, 0, 0, 0)
+      {
+        append<T, type_traits<T>::db_type_id> (v);
+      }
+
+      template <typename T>
+      explicit
+      query (ref_bind<T> r)
+        : binding_ (0, 0), native_binding_ (0, 0, 0, 0)
+      {
+        append<T, type_traits<T>::db_type_id> (r);
+      }
+
+      template <database_type_id ID>
+      query (const query_column<bool, ID>&);
+
+      query (const query&);
+
+      query&
+      operator= (const query&);
+
+    public:
+      std::string
+      clause () const;
+
+      binding&
+      parameters_binding () const;
+
+      native_binding&
+      native_parameters_binding () const
+      {
+        return native_binding_;
+      }
+
+      const unsigned int*
+      parameter_types () const
+      {
+        return types_.empty () ? 0 : &types_[0];
+      }
+
+      std::size_t
+      parameter_count () const
+      {
+        return parameters_.size ();
+      }
+
+    public:
+      template <typename T>
+      static val_bind<T>
+      _val (const T& x)
+      {
+        return val_bind<T> (x);
+      }
+
+      template <typename T>
+      static ref_bind<T>
+      _ref (const T& x)
+      {
+        return ref_bind<T> (x);
+      }
+
+    public:
+      query&
+      operator+= (const query&);
+
+      query&
+      operator+= (const std::string& q)
+      {
+        size_t n (clause_.size ());
+
+        if (n != 0 && clause_[n - 1] != ' ' && !q.empty () && q[0] != ' ')
+          clause_ += ' ';
+
+        clause_ += q;
+        return *this;
+      }
+
+      template <typename T>
+      query&
+      operator+= (val_bind<T> v)
+      {
+        append<T, type_traits<T>::db_type_id> (v);
+        return *this;
+      }
+
+      template <typename T>
+      query&
+      operator+= (ref_bind<T> r)
+      {
+        append<T, type_traits<T>::db_type_id> (r);
+        return *this;
+      }
+
+    public:
+      template <typename T, database_type_id ID>
+      void
+      append (val_bind<T>);
+
+      template <typename T, database_type_id ID>
+      void
+      append (ref_bind<T>);
+
+    private:
+      void
+      add (details::shared_ptr<query_param>);
+
+    private:
+      typedef std::vector<details::shared_ptr<query_param> > parameters_type;
+
+      std::string clause_;
+      parameters_type parameters_;
+
+      mutable std::vector<bind> bind_;
+      mutable binding binding_;
+
+      std::vector<char*> values_;
+      std::vector<int> lengths_;
+      std::vector<int> formats_;
+      std::vector<unsigned int> types_;
+      mutable native_binding native_binding_;
+    };
+
+    inline query
+    operator+ (const query& x, const query& y)
+    {
+      query r (x);
+      r += y;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (const query& q, val_bind<T> b)
+    {
+      query r (q);
+      r += b;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (const query& q, ref_bind<T> b)
+    {
+      query r (q);
+      r += b;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (val_bind<T> b, const query& q)
+    {
+      query r;
+      r += b;
+      r += q;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (ref_bind<T> b, const query& q)
+    {
+      query r;
+      r += b;
+      r += q;
+      return r;
+    }
+
+    inline query
+    operator+ (const query& q, const std::string& s)
+    {
+      query r (q);
+      r += s;
+      return r;
+    }
+
+    inline query
+    operator+ (const std::string& s, const query& q)
+    {
+      query r (s);
+      r += q;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (const std::string& s, val_bind<T> b)
+    {
+      query r (s);
+      r += b;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (const std::string& s, ref_bind<T> b)
+    {
+      query r (s);
+      r += b;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (val_bind<T> b, const std::string& s)
+    {
+      query r;
+      r += b;
+      r += s;
+      return r;
+    }
+
+    template <typename T>
+    inline query
+    operator+ (ref_bind<T> b, const std::string& s)
+    {
+      query r;
+      r += b;
+      r += s;
+      return r;
+    }
+
+    inline query
+    operator&& (const query& x, const query& y)
+    {
+      query r ("(");
+      r += x;
+      r += ") AND (";
+      r += y;
+      r += ")";
+      return r;
+    }
+
+    inline query
+    operator|| (const query& x, const query& y)
+    {
+      query r ("(");
+      r += x;
+      r += ") OR (";
+      r += y;
+      r += ")";
+      return r;
+    }
+
+    inline query
+    operator! (const query& x)
+    {
+      query r ("NOT (");
+      r += x;
+      r += ")";
+      return r;
+    }
+
+    // query_column
+    //
+
+    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
+    {
+      explicit
+      query_column (const char* name)
+          : name_ (name)
+      {
+      }
+
+      const char*
+      name () const
+      {
+        return name_;
+      }
+
+      // is_null, is_not_null
+      //
+    public:
+      query
+      is_null () const
+      {
+        query q (name_);
+        q += "IS NULL";
+        return q;
+      }
+
+      query
+      is_not_null () const
+      {
+        query q (name_);
+        q += "IS NOT NULL";
+        return q;
+      }
+
+      // in
+      //
+    public:
+      query
+      in (const T&, const T&) const;
+
+      query
+      in (const T&, const T&, const T&) const;
+
+      query
+      in (const T&, const T&, const T&, const T&) const;
+
+      query
+      in (const T&, const T&, const T&, const T&, const T&) const;
+
+      template <typename I>
+      query
+      in_range (I begin, I end) const;
+
+      // =
+      //
+    public:
+      query
+      equal (const T& v) const
+      {
+        return equal (val_bind<T> (v));
+      }
+
+      query
+      equal (val_bind<T> v) const
+      {
+        query q (name_);
+        q += "=";
+        q.append<T, ID> (v);
+        return q;
+      }
+
+      template <typename T2>
+      query
+      equal (val_bind<T2> v) const
+      {
+        copy_bind<T, T2> c (v.val);
+        return equal (c);
+      }
+
+      query
+      equal (ref_bind<T> r) const
+      {
+        query q (name_);
+        q += "=";
+        q.append<T, ID> (r);
+        return q;
+      }
+
+      friend query
+      operator== (const query_column& c, const T& v)
+      {
+        return c.equal (v);
+      }
+
+      friend query
+      operator== (const T& v, const query_column& c)
+      {
+        return c.equal (v);
+      }
+
+      friend query
+      operator== (const query_column& c, val_bind<T> v)
+      {
+        return c.equal (v);
+      }
+
+      friend query
+      operator== (val_bind<T> v, const query_column& c)
+      {
+        return c.equal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator== (const query_column& c, val_bind<T2> v)
+      {
+        return c.equal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator== (val_bind<T2> v, const query_column& c)
+      {
+        return c.equal (v);
+      }
+
+      friend query
+      operator== (const query_column& c, ref_bind<T> r)
+      {
+        return c.equal (r);
+      }
+
+      friend query
+      operator== (ref_bind<T> r, const query_column& c)
+      {
+        return c.equal (r);
+      }
+
+      // !=
+      //
+    public:
+      query
+      unequal (const T& v) const
+      {
+        return unequal (val_bind<T> (v));
+      }
+
+      query
+      unequal (val_bind<T> v) const
+      {
+        query q (name_);
+        q += "!=";
+        q.append<T, ID> (v);
+        return q;
+      }
+
+      template <typename T2>
+      query
+      unequal (val_bind<T2> v) const
+      {
+        copy_bind<T, T2> c (v.val);
+        return unequal (c);
+      }
+
+      query
+      unequal (ref_bind<T> r) const
+      {
+        query q (name_);
+        q += "!=";
+        q.append<T, ID> (r);
+        return q;
+      }
+
+      friend query
+      operator!= (const query_column& c, const T& v)
+      {
+        return c.unequal (v);
+      }
+
+      friend query
+      operator!= (const T& v, const query_column& c)
+      {
+        return c.unequal (v);
+      }
+
+      friend query
+      operator!= (const query_column& c, val_bind<T> v)
+      {
+        return c.unequal (v);
+      }
+
+      friend query
+      operator!= (val_bind<T> v, const query_column& c)
+      {
+        return c.unequal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator!= (const query_column& c, val_bind<T2> v)
+      {
+        return c.unequal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator!= (val_bind<T2> v, const query_column& c)
+      {
+        return c.unequal (v);
+      }
+
+      friend query
+      operator!= (const query_column& c, ref_bind<T> r)
+      {
+        return c.unequal (r);
+      }
+
+      friend query
+      operator!= (ref_bind<T> r, const query_column& c)
+      {
+        return c.unequal (r);
+      }
+
+      // <
+      //
+    public:
+      query
+      less (const T& v) const
+      {
+        return less (val_bind<T> (v));
+      }
+
+      query
+      less (val_bind<T> v) const
+      {
+        query q (name_);
+        q += "<";
+        q.append<T, ID> (v);
+        return q;
+      }
+
+      template <typename T2>
+      query
+      less (val_bind<T2> v) const
+      {
+        copy_bind<T, T2> c (v.val);
+        return less (c);
+      }
+
+      query
+      less (ref_bind<T> r) const
+      {
+        query q (name_);
+        q += "<";
+        q.append<T, ID> (r);
+        return q;
+      }
+
+      friend query
+      operator< (const query_column& c, const T& v)
+      {
+        return c.less (v);
+      }
+
+      friend query
+      operator< (const T& v, const query_column& c)
+      {
+        return c.greater (v);
+      }
+
+      friend query
+      operator< (const query_column& c, val_bind<T> v)
+      {
+        return c.less (v);
+      }
+
+      friend query
+      operator< (val_bind<T> v, const query_column& c)
+      {
+        return c.greater (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator< (const query_column& c, val_bind<T2> v)
+      {
+        return c.less (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator< (val_bind<T2> v, const query_column& c)
+      {
+        return c.greater (v);
+      }
+
+      friend query
+      operator< (const query_column& c, ref_bind<T> r)
+      {
+        return c.less (r);
+      }
+
+      friend query
+      operator< (ref_bind<T> r, const query_column& c)
+      {
+        return c.greater (r);
+      }
+
+      // >
+      //
+    public:
+      query
+      greater (const T& v) const
+      {
+        return greater (val_bind<T> (v));
+      }
+
+      query
+      greater (val_bind<T> v) const
+      {
+        query q (name_);
+        q += ">";
+        q.append<T, ID> (v);
+        return q;
+      }
+
+      template <typename T2>
+      query
+      greater (val_bind<T2> v) const
+      {
+        copy_bind<T, T2> c (v.val);
+        return greater (c);
+      }
+
+      query
+      greater (ref_bind<T> r) const
+      {
+        query q (name_);
+        q += ">";
+        q.append<T, ID> (r);
+        return q;
+      }
+
+      friend query
+      operator> (const query_column& c, const T& v)
+      {
+        return c.greater (v);
+      }
+
+      friend query
+      operator> (const T& v, const query_column& c)
+      {
+        return c.less (v);
+      }
+
+      friend query
+      operator> (const query_column& c, val_bind<T> v)
+      {
+        return c.greater (v);
+      }
+
+      friend query
+      operator> (val_bind<T> v, const query_column& c)
+      {
+        return c.less (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator> (const query_column& c, val_bind<T2> v)
+      {
+        return c.greater (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator> (val_bind<T2> v, const query_column& c)
+      {
+        return c.less (v);
+      }
+
+      friend query
+      operator> (const query_column& c, ref_bind<T> r)
+      {
+        return c.greater (r);
+      }
+
+      friend query
+      operator> (ref_bind<T> r, const query_column& c)
+      {
+        return c.less (r);
+      }
+
+      // <=
+      //
+    public:
+      query
+      less_equal (const T& v) const
+      {
+        return less_equal (val_bind<T> (v));
+      }
+
+      query
+      less_equal (val_bind<T> v) const
+      {
+        query q (name_);
+        q += "<=";
+        q.append<T, ID> (v);
+        return q;
+      }
+
+      template <typename T2>
+      query
+      less_equal (val_bind<T2> v) const
+      {
+        copy_bind<T, T2> c (v.val);
+        return less_equal (c);
+      }
+
+      query
+      less_equal (ref_bind<T> r) const
+      {
+        query q (name_);
+        q += "<=";
+        q.append<T, ID> (r);
+        return q;
+      }
+
+      friend query
+      operator<= (const query_column& c, const T& v)
+      {
+        return c.less_equal (v);
+      }
+
+      friend query
+      operator<= (const T& v, const query_column& c)
+      {
+        return c.greater_equal (v);
+      }
+
+      friend query
+      operator<= (const query_column& c, val_bind<T> v)
+      {
+        return c.less_equal (v);
+      }
+
+      friend query
+      operator<= (val_bind<T> v, const query_column& c)
+      {
+        return c.greater_equal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator<= (const query_column& c, val_bind<T2> v)
+      {
+        return c.less_equal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator<= (val_bind<T2> v, const query_column& c)
+      {
+        return c.greater_equal (v);
+      }
+
+      friend query
+      operator<= (const query_column& c, ref_bind<T> r)
+      {
+        return c.less_equal (r);
+      }
+
+      friend query
+      operator<= (ref_bind<T> r, const query_column& c)
+      {
+        return c.greater_equal (r);
+      }
+
+      // >=
+      //
+    public:
+      query
+      greater_equal (const T& v) const
+      {
+        return greater_equal (val_bind<T> (v));
+      }
+
+      query
+      greater_equal (val_bind<T> v) const
+      {
+        query q (name_);
+        q += ">=";
+        q.append<T, ID> (v);
+        return q;
+      }
+
+      template <typename T2>
+      query
+      greater_equal (val_bind<T2> v) const
+      {
+        copy_bind<T, T2> c (v.val);
+        return greater_equal (c);
+      }
+
+      query
+      greater_equal (ref_bind<T> r) const
+      {
+        query q (name_);
+        q += ">=";
+        q.append<T, ID> (r);
+        return q;
+      }
+
+      friend query
+      operator>= (const query_column& c, const T& v)
+      {
+        return c.greater_equal (v);
+      }
+
+      friend query
+      operator>= (const T& v, const query_column& c)
+      {
+        return c.less_equal (v);
+      }
+
+      friend query
+      operator>= (const query_column& c, val_bind<T> v)
+      {
+        return c.greater_equal (v);
+      }
+
+      friend query
+      operator>= (val_bind<T> v, const query_column& c)
+      {
+        return c.less_equal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator>= (const query_column& c, val_bind<T2> v)
+      {
+        return c.greater_equal (v);
+      }
+
+      template <typename T2>
+      friend query
+      operator>= (val_bind<T2> v, const query_column& c)
+      {
+        return c.less_equal (v);
+      }
+
+      friend query
+      operator>= (const query_column& c, ref_bind<T> r)
+      {
+        return c.greater_equal (r);
+      }
+
+      friend query
+      operator>= (ref_bind<T> r, const query_column& c)
+      {
+        return c.less_equal (r);
+      }
+
+      // Column comparison.
+      //
+    public:
+      template <typename T2, database_type_id ID2>
+      query
+      operator== (const query_column<T2, ID2>& c) const
+      {
+        // We can compare columns only if we can compare their C++ types.
+        //
+        (void) (sizeof (type_instance<T> () == type_instance<T2> ()));
+
+        query q (name_);
+        q += "=";
+        q += c.name ();
+        return q;
+      }
+
+      template <typename T2, database_type_id ID2>
+      query
+      operator!= (const query_column<T2, ID2>& c) const
+      {
+        // We can compare columns only if we can compare their C++ types.
+        //
+        (void) (sizeof (type_instance<T> () != type_instance<T2> ()));
+
+        query q (name_);
+        q += "!=";
+        q += c.name ();
+        return q;
+      }
+
+      template <typename T2, database_type_id ID2>
+      query
+      operator< (const query_column<T2, ID2>& c) const
+      {
+        // We can compare columns only if we can compare their C++ types.
+        //
+        (void) (sizeof (type_instance<T> () < type_instance<T2> ()));
+
+        query q (name_);
+        q += "<";
+        q += c.name ();
+        return q;
+      }
+
+      template <typename T2, database_type_id ID2>
+      query
+      operator> (const query_column<T2, ID2>& c) const
+      {
+        // We can compare columns only if we can compare their C++ types.
+        //
+        (void) (sizeof (type_instance<T> () > type_instance<T2> ()));
+
+        query q (name_);
+        q += ">";
+        q += c.name ();
+        return q;
+      }
+
+      template <typename T2, database_type_id ID2>
+      query
+      operator<= (const query_column<T2, ID2>& c) const
+      {
+        // We can compare columns only if we can compare their C++ types.
+        //
+        (void) (sizeof (type_instance<T> () <= type_instance<T2> ()));
+
+        query q (name_);
+        q += "<=";
+        q += c.name ();
+        return q;
+      }
+
+      template <typename T2, database_type_id ID2>
+      query
+      operator>= (const query_column<T2, ID2>& c) const
+      {
+        // We can compare columns only if we can compare their C++ types.
+        //
+        (void) (sizeof (type_instance<T> () >= type_instance<T2> ()));
+
+        query q (name_);
+        q += ">=";
+        q += c.name ();
+        return q;
+      }
+
+    private:
+      const char* name_;
+    };
+
+    //
+    //
+    template <typename T, database_type_id>
+    struct query_param_impl;
+
+    // BOOLEAN
+    //
+    template <typename T>
+    struct query_param_impl<T, id_boolean>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::boolean;
+        b->buffer = &image_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return bool_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_boolean>::set_image (image_, dummy, v);
+      }
+
+    private:
+      bool image_;
+    };
+
+    // SMALLINT
+    //
+    template <typename T>
+    struct query_param_impl<T, id_smallint>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::smallint;
+        b->buffer = &image_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return int2_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_smallint>::set_image (image_, dummy, v);
+      }
+
+    private:
+      short image_;
+    };
+
+    // INTEGER
+    //
+    template <typename T>
+    struct query_param_impl<T, id_integer>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::integer;
+        b->buffer = &image_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return int4_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_integer>::set_image (image_, dummy, v);
+      }
+
+    private:
+      int image_;
+    };
+
+    // BIGINT
+    //
+    template <typename T>
+    struct query_param_impl<T, id_bigint>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::bigint;
+        b->buffer = &image_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return int8_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_bigint>::set_image (image_, dummy, v);
+      }
+
+    private:
+      long long image_;
+    };
+
+    // REAL
+    //
+    template <typename T>
+    struct query_param_impl<T, id_real>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::real;
+        b->buffer = &image_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return float4_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_real>::set_image (image_, dummy, v);
+      }
+
+    private:
+      float image_;
+    };
+
+    // DOUBLE
+    //
+    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 (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::double_;
+        b->buffer = &image_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return float8_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_double>::set_image (image_, dummy, v);
+      }
+
+    private:
+      double image_;
+    };
+
+    // @@ NUMERIC
+    //
+    // template <typename T>
+    // struct query_param_impl<T, id_numeric>: query_param
+    // {
+    //   query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+    //   query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+    //   virtual bool
+    //   init ()
+    //   {
+    //     return init (*static_cast<const T*> (value_));
+    //   }
+
+    //   virtual void
+    //   bind (pgsql::bind* b)
+    //   {
+    //     b->type = bind::numeric;
+    //     b->buffer = buffer_.data ();
+    //     b->buffer_length = static_cast<unsigned long> (buffer_.capacity ());
+    //     b->length = &size_;
+    //   }
+
+    // private:
+    //   bool
+    //   init (const T& v)
+    //   {
+    //     bool dummy;
+    //     std::size_t size, cap (buffer_.capacity ());
+    //     value_traits<T, id_decimal>::set_image (buffer_, size, dummy, v);
+    //     size_ = static_cast<unsigned long> (size);
+    //     return cap != buffer_.capacity ();
+    //   }
+
+    // private:
+    //   details::buffer buffer_;
+    //   unsigned long size_;
+    // };
+
+    // @@ DATE
+    //
+    // 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 (val_bind<T> v) : query_param (0) {init (v.val);}
+
+    //   virtual bool
+    //   init ()
+    //   {
+    //     init (*static_cast<const T*> (value_));
+    //     return false;
+    //   }
+
+    //   virtual void
+    //   bind (MYSQL_BIND* b)
+    //   {
+    //     b->buffer_type = MYSQL_TYPE_DATE;
+    //     b->buffer = &image_;
+    //   }
+
+    // private:
+    //   void
+    //   init (const T& v)
+    //   {
+    //     bool dummy;
+    //     value_traits<T, id_date>::set_image (image_, dummy, v);
+    //   }
+
+    // private:
+    //   MYSQL_TIME image_;
+    // };
+
+    // @@ TIME
+    //
+    // template <typename T>
+    // struct query_param_impl<T, id_time>: query_param
+    // {
+    //   query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+    //   query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+    //   virtual bool
+    //   init ()
+    //   {
+    //     init (*static_cast<const T*> (value_));
+    //     return false;
+    //   }
+
+    //   virtual void
+    //   bind (MYSQL_BIND* b)
+    //   {
+    //     b->buffer_type = MYSQL_TYPE_TIME;
+    //     b->buffer = &image_;
+    //   }
+
+    // private:
+    //   void
+    //   init (const T& v)
+    //   {
+    //     bool dummy;
+    //     value_traits<T, id_time>::set_image (image_, dummy, v);
+    //   }
+
+    // private:
+    //   MYSQL_TIME image_;
+    // };
+
+    // @@ TIMESTAMP
+    //
+    // template <typename T>
+    // struct query_param_impl<T, id_timestamp>: query_param
+    // {
+    //   query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+    //   query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+    //   virtual bool
+    //   init ()
+    //   {
+    //     init (*static_cast<const T*> (value_));
+    //     return false;
+    //   }
+
+    //   virtual void
+    //   bind (MYSQL_BIND* b)
+    //   {
+    //     b->buffer_type = MYSQL_TYPE_TIMESTAMP;
+    //     b->buffer = &image_;
+    //   }
+
+    // private:
+    //   void
+    //   init (const T& v)
+    //   {
+    //     bool dummy;
+    //     value_traits<T, id_timestamp>::set_image (image_, dummy, v);
+    //   }
+
+    // private:
+    //   MYSQL_TIME image_;
+    // };
+
+    // STRING
+    //
+    template <typename T>
+    struct query_param_impl<T, id_string>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        return init (*static_cast<const T*> (value_));
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::text;
+        b->buffer = buffer_.data ();
+        b->capacity = buffer_.capacity ();
+        b->size = &size_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return text_oid;
+      }
+
+    private:
+      bool
+      init (const T& v)
+      {
+        bool dummy;
+        std::size_t size, cap (buffer_.capacity ());
+        value_traits<T, id_string>::set_image (buffer_, size, dummy, v);
+        size_ = size;
+        return cap != buffer_.capacity ();
+      }
+
+    private:
+      details::buffer buffer_;
+      std::size_t size_;
+    };
+
+    // BYTEA
+    //
+    template <typename T>
+    struct query_param_impl<T, id_bytea>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        return init (*static_cast<const T*> (value_));
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::bytea;
+        b->buffer = buffer_.data ();
+        b->capacity = buffer_.capacity ();
+        b->size = &size_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return bytea_oid;
+      }
+
+    private:
+      bool
+      init (const T& v)
+      {
+        bool dummy;
+        std::size_t size, cap (buffer_.capacity ());
+        value_traits<T, id_bytea>::set_image (buffer_, size, dummy, v);
+        size_ = size;
+        return cap != buffer_.capacity ();
+      }
+
+    private:
+      details::buffer buffer_;
+      std::size_t size_;
+    };
+
+    // @@ BIT
+    //
+    // template <typename T>
+    // struct query_param_impl<T, id_bit>: query_param
+    // {
+    //   query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+    //   query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+    //   virtual bool
+    //   init ()
+    //   {
+    //     init (*static_cast<const T*> (value_));
+    //     return false;
+    //   }
+
+    //   virtual void
+    //   bind (pgsql::bind* b)
+    //   {
+    //     b->type = bind::bit;
+    //     b->buffer = buffer_;
+    //     b->capacity = sizeof (buffer_);
+    //     b->size = &size_;
+    //   }
+
+    // private:
+    //   void
+    //   init (const T& v)
+    //   {
+    //     bool dummy;
+    //     std::size_t size;
+    //     value_traits<T, id_bit>::set_image (
+    //       buffer_, sizeof (buffer_), size, dummy, v);
+    //     size_ = static_cast<unsigned long> (size);
+    //   }
+
+    // private:
+    //   // Max 64 bit.
+    //   //
+    //   unsigned char buffer_[8];
+    //   unsigned long size_;
+    // };
+
+    // VARBIT
+    //
+    template <typename T>
+    struct query_param_impl<T, id_varbit>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        return init (*static_cast<const T*> (value_));
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::varbit;
+        b->buffer = buffer_.data ();
+        b->capacity = buffer_.capacity ();
+        b->size = &size_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return varbit_oid;
+      }
+
+    private:
+      bool
+      init (const T& v)
+      {
+        bool dummy;
+        std::size_t size, cap (buffer_.capacity ());
+        value_traits<T, id_varbit>::set_image (buffer_, size, dummy, v);
+        size_ = size;
+        return cap != buffer_.capacity ();
+      }
+
+    private:
+      details::buffer buffer_;
+      std::size_t size_;
+    };
+
+    // UUID
+    //
+    template <typename T>
+    struct query_param_impl<T, id_uuid>: query_param
+    {
+      query_param_impl (ref_bind<T> r) : query_param (&r.ref) {}
+      query_param_impl (val_bind<T> v) : query_param (0) {init (v.val);}
+
+      virtual bool
+      init ()
+      {
+        init (*static_cast<const T*> (value_));
+        return false;
+      }
+
+      virtual void
+      bind (pgsql::bind* b)
+      {
+        b->type = bind::uuid;
+        b->buffer = buffer_;
+      }
+
+      virtual unsigned int
+      oid () const
+      {
+        return uuid_oid;
+      }
+
+    private:
+      void
+      init (const T& v)
+      {
+        bool dummy;
+        value_traits<T, id_uuid>::set_image (buffer_, dummy, v);
+      }
+
+    private:
+      unsigned char buffer_[16];
+    };
+  }
+}
+
+// odb::query specialization for PostgreSQL.
+//
+namespace odb
+{
+  template <typename T>
+  class query<T, pgsql::query>: public object_traits<T>::query_type
+  {
+  public:
+    // We don't define any typedefs here since they may clash with
+    // column names defined by our base type.
+    //
+
+    query ()
+    {
+    }
+
+    explicit
+    query (const std::string& q)
+        : object_traits<T>::query_type (q)
+    {
+    }
+
+    template <typename T2>
+    explicit
+    query (pgsql::val_bind<T2> v)
+        : object_traits<T>::query_type (pgsql::query (v))
+    {
+    }
+
+    template <typename T2>
+    explicit
+    query (pgsql::ref_bind<T2> r)
+        : object_traits<T>::query_type (pgsql::query (r))
+    {
+    }
+
+    query (const pgsql::query& q)
+        : object_traits<T>::query_type (q)
+    {
+    }
+
+    template <pgsql::database_type_id ID>
+    query (const pgsql::query_column<bool, ID>& qc)
+        : object_traits<T>::query_type (qc)
+    {
+    }
+  };
+}
+
+#include <odb/pgsql/query.ixx>
+#include <odb/pgsql/query.txx>
+
+#include <odb/post.hxx>
+
+#endif // ODB_PGSQL_QUERY_HXX
diff --git a/odb/pgsql/query.ixx b/odb/pgsql/query.ixx
new file mode 100644
index 0000000..05561a2
--- /dev/null
+++ b/odb/pgsql/query.ixx
@@ -0,0 +1,28 @@
+// file      : odb/pgsql/query.ixx
+// author    : Constantin Michael <constantin@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+namespace odb
+{
+  namespace pgsql
+  {
+    template <typename T, database_type_id ID>
+    inline void query::
+    append (val_bind<T> v)
+    {
+      add (
+        details::shared_ptr<query_param> (
+          new (details::shared) query_param_impl<T, ID> (v)));
+    }
+
+    template <typename T, database_type_id ID>
+    inline void query::
+    append (ref_bind<T> r)
+    {
+      add (
+        details::shared_ptr<query_param> (
+          new (details::shared) query_param_impl<T, ID> (r)));
+    }
+  }
+}
diff --git a/odb/pgsql/query.txx b/odb/pgsql/query.txx
new file mode 100644
index 0000000..7d80f2b
--- /dev/null
+++ b/odb/pgsql/query.txx
@@ -0,0 +1,110 @@
+// file      : odb/pgsql/query.txx
+// author    : Constantin Michael <constantin@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+namespace odb
+{
+  namespace pgsql
+  {
+    // query
+    //
+
+    template <database_type_id ID>
+    query::
+    query (const query_column<bool, ID>& c)
+        : clause_ (c.name ()), binding_ (0, 0), native_binding_ (0, 0, 0, 0)
+    {
+      // Cannot use IS TRUE here since database type can be a non-
+      // integral type.
+      //
+      clause_ += " = ";
+      append<bool, ID> (val_bind<bool> (true));
+    }
+
+    // query_column
+    //
+    template <typename T, database_type_id ID>
+    query query_column<T, ID>::
+    in (const T& v1, const T& v2) const
+    {
+      query q (name_);
+      q += "IN (";
+      q.append<T, ID> (val_bind<T> (v1));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v2));
+      q += ")";
+      return q;
+    }
+
+    template <typename T, database_type_id ID>
+    query query_column<T, ID>::
+    in (const T& v1, const T& v2, const T& v3) const
+    {
+      query q (name_);
+      q += "IN (";
+      q.append<T, ID> (val_bind<T> (v1));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v2));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v3));
+      q += ")";
+      return q;
+    }
+
+    template <typename T, database_type_id ID>
+    query query_column<T, ID>::
+    in (const T& v1, const T& v2, const T& v3, const T& v4) const
+    {
+      query q (name_);
+      q += "IN (";
+      q.append<T, ID> (val_bind<T> (v1));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v2));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v3));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v4));
+      q += ")";
+      return q;
+    }
+
+    template <typename T, database_type_id ID>
+    query query_column<T, ID>::
+    in (const T& v1, const T& v2, const T& v3, const T& v4, const T& v5) const
+    {
+      query q (name_);
+      q += "IN (";
+      q.append<T, ID> (val_bind<T> (v1));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v2));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v3));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v4));
+      q += ",";
+      q.append<T, ID> (val_bind<T> (v5));
+      q += ")";
+      return q;
+    }
+
+    template <typename T, database_type_id ID>
+    template <typename I>
+    query query_column<T, ID>::
+    in_range (I begin, I end) const
+    {
+      query q (name_);
+      q += "IN (";
+
+      for (I i (begin); i != end; ++i)
+      {
+        if (i != begin)
+          q += ",";
+
+        q.append<T, ID> (val_bind<T> (*i));
+      }
+      q += ")";
+      return q;
+    }
+  }
+}
diff --git a/odb/pgsql/result.hxx b/odb/pgsql/result.hxx
new file mode 100644
index 0000000..9510680
--- /dev/null
+++ b/odb/pgsql/result.hxx
@@ -0,0 +1,78 @@
+// file      : odb/pgsql/result.hxx
+// author    : Constantin Michael <constantin@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#ifndef ODB_PGSQL_RESULT_HXX
+#define ODB_PGSQL_RESULT_HXX
+
+#include <odb/pre.hxx>
+
+#include <cstddef> // std::size_t
+
+#include <odb/result.hxx>
+#include <odb/details/shared-ptr.hxx>
+
+#include <odb/pgsql/version.hxx>
+#include <odb/pgsql/forward.hxx> // query, query_params
+#include <odb/pgsql/statement.hxx>
+
+#include <odb/pgsql/details/export.hxx>
+
+namespace odb
+{
+  namespace pgsql
+  {
+    template <typename T>
+    class result_impl: public odb::result_impl<T>
+    {
+    public:
+      typedef typename odb::result_impl<T>::pointer_type pointer_type;
+      typedef typename odb::result_impl<T>::pointer_traits pointer_traits;
+
+      typedef typename odb::result_impl<T>::object_type object_type;
+      typedef typename odb::result_impl<T>::id_type id_type;
+      typedef typename odb::result_impl<T>::object_traits object_traits;
+
+
+      virtual
+      ~result_impl ();
+
+      result_impl (const query&,
+                   details::shared_ptr<select_statement>,
+                   object_statements<object_type>&);
+
+      virtual void
+      load (object_type&);
+
+      virtual id_type
+      load_id ();
+
+      virtual void
+      next ();
+
+      virtual void
+      cache ();
+
+      virtual std::size_t
+      size ();
+
+      using odb::result_impl<T>::current;
+
+    private:
+      void
+      load_image ();
+
+    private:
+      details::shared_ptr<select_statement> statement_;
+      object_statements<object_type>& statements_;
+      std::size_t count_;
+    };
+  }
+}
+
+#include <odb/pgsql/result.txx>
+
+#include <odb/post.hxx>
+
+#endif // ODB_PGSQL_RESULT_HXX
diff --git a/odb/pgsql/result.txx b/odb/pgsql/result.txx
new file mode 100644
index 0000000..f96fe81
--- /dev/null
+++ b/odb/pgsql/result.txx
@@ -0,0 +1,134 @@
+// file      : odb/pgsql/result.txx
+// author    : Constantin Michael <constantin@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#include <odb/exceptions.hxx>
+
+namespace odb
+{
+  namespace pgsql
+  {
+    template <typename T>
+    result_impl<T>::
+    ~result_impl ()
+    {
+    }
+
+    template <typename T>
+    result_impl<T>::
+    result_impl (const query&,
+                 details::shared_ptr<select_statement> st,
+                 object_statements<object_type>& sts)
+        : odb::result_impl<T> (sts.connection ().database ()),
+          statement_ (st),
+          statements_ (sts),
+          count_ (0)
+    {
+    }
+
+    template <typename T>
+    void result_impl<T>::
+    load (object_type& obj)
+    {
+      load_image ();
+
+      // This is a top-level call so the statements cannot be locked.
+      //
+      assert (!statements_.locked ());
+      typename object_statements<object_type>::auto_lock l (statements_);
+
+      typename object_traits::image_type& i (statements_.image ());
+      object_traits::init (obj, i, this->database ());
+
+      // Initialize the id image and binding and load the rest of the object
+      // (containers, etc).
+      //
+      typename object_traits::id_image_type& idi (statements_.id_image ());
+      object_traits::init (idi, object_traits::id (i));
+
+      binding& idb (statements_.id_image_binding ());
+      if (idi.version != statements_.id_image_version () || idb.version == 0)
+      {
+        object_traits::bind (idb.bind, idi);
+        statements_.id_image_version (idi.version);
+        idb.version++;
+      }
+
+      object_traits::load_ (statements_, obj);
+
+      statements_.load_delayed ();
+      l.unlock ();
+    }
+
+    template <typename T>
+    typename result_impl<T>::id_type result_impl<T>::
+    load_id ()
+    {
+      load_image ();
+      return object_traits::id (statements_.image ());
+    }
+
+    template <typename T>
+    void result_impl<T>::
+    next ()
+    {
+      this->current (pointer_type ());
+
+      // Increment the position and postpone the actual row fetching
+      // until later. This way if the same object is loaded in between
+      // iteration, the image won't be messed up.
+      //
+      if (++count_ > statement_->result_size ())
+        this->end_ = true;
+    }
+
+    template <typename T>
+    void result_impl<T>::
+    load_image ()
+    {
+      // The image can grow between calls to load() as a result of other
+      // statements execution.
+      //
+      typename object_traits::image_type& im (statements_.image ());
+
+      if (im.version != statements_.out_image_version ())
+      {
+        binding& b (statements_.out_image_binding ());
+        object_traits::bind (b.bind, im, true);
+        statements_.out_image_version (im.version);
+        b.version++;
+      }
+
+      select_statement::result r (statement_->fetch ());
+
+      if (r == select_statement::truncated)
+      {
+        if (object_traits::grow (im, statements_.out_image_truncated ()))
+          im.version++;
+
+        if (im.version != statements_.out_image_version ())
+        {
+          binding& b (statements_.out_image_binding ());
+          object_traits::bind (b.bind, im, true);
+          statements_.out_image_version (im.version);
+          b.version++;
+          statement_->refetch ();
+        }
+      }
+    }
+
+    template <typename T>
+    void result_impl<T>::
+    cache ()
+    {
+    }
+
+    template <typename T>
+    std::size_t result_impl<T>::
+    size ()
+    {
+      return statement_->result_size ();
+    }
+  }
+}