diff --git a/table.cpp b/table.cpp
index 920c3720c..d3d0e17ae 100644
--- a/table.cpp
+++ b/table.cpp
@@ -47,6 +47,7 @@ table_t::table_t(table_t const &other,
     // this would be premature.
     if (other.sql_conn) {
         connect();
+        prepare();
     }
 }
 
@@ -171,6 +172,11 @@ void table_t::start(std::string const &conninfo,
         //TODO: change the type of the geometry column if needed - this can only change to a more permissive type
     }
 
+    prepare();
+}
+
+void table_t::prepare()
+{
     //let postgres cache this query as it will presumably happen a lot
     pgsql_exec_simple(sql_conn, PGRES_COMMAND_OK,
                       (fmt("PREPARE get_wkb (" POSTGRES_OSMID_TYPE
diff --git a/table.hpp b/table.hpp
index a08264b91..b656ddc95 100644
--- a/table.hpp
+++ b/table.hpp
@@ -71,6 +71,7 @@ class table_t
 
     protected:
         void connect();
+        void prepare();
         void teardown();
 
         void write_columns(taglist_t const &tags, std::vector<bool> *used);