Add odb::connection class

This abstract class represents a connection to the database. One can
use it to start a transaction or to execute a native statement out
of a transaction.

Before we had concrete connection classes in the database runtime
libraries (e.g., odb::mysql::connection). Now these classes derive
from odb::connection.

1 files changed, 7 insertions, 0 deletions

diff --git a/odb/sqlite/forward.hxx b/odb/sqlite/forward.hxx
index 63c3be4..a4e3376 100644
--- a/odb/sqlite/forward.hxx
+++ b/odb/sqlite/forward.hxx
@@ -16,6 +16,7 @@ namespace odb
   {
     class database;
     class connection;
+    typedef details::shared_ptr<connection> connection_ptr;
     class connection_factory;
     class transaction;
     class query;
@@ -37,6 +38,12 @@ namespace odb
   namespace details
   {
     template <>
+    struct counter_type<sqlite::connection>
+    {
+      typedef shared_base counter;
+    };
+
+    template <>
     struct counter_type<sqlite::query_params>
     {
       typedef shared_base counter;