diff --git a/R/Connect.R b/R/Connect.R
index 9e330e82..7e4dc406 100644
--- a/R/Connect.R
+++ b/R/Connect.R
@@ -760,22 +760,7 @@ connectUsingJdbcDriver <- function(jdbcDriver,
       abort(paste0("Unable to connect JDBC to ", url, " (", rJava::.jcall(x, "S", "getMessage"), ")"))
     }
   }
-  class <- getClassDef("Microsoft SQL Server", where = class_cache, inherits = FALSE)
-  if (is.null(class) || methods::isVirtualClass(class)) {
-    setClass("Microsoft SQL Server",
-             contains = "DBIConnection", 
-             where = class_cache)
-  }
-  class <- getClassDef("DatabaseConnectorConnection", where = class_cache, inherits = FALSE)
-  if (is.null(class) || methods::isVirtualClass(class)) {
-    setClass("DatabaseConnectorConnection", 
-             contains = "Microsoft SQL Server",
-             slots = list(
-               identifierQuote = "character",
-               stringQuote = "character", dbms = "character", uuid = "character"
-             ),
-             where = class_cache)
-  }
+  ensureDatabaseConnectorConnectionClassExists()
   class <- getClassDef("DatabaseConnectorJdbcConnection", where = class_cache, inherits = FALSE)
   if (is.null(class) || methods::isVirtualClass(class)) {
     setClass("DatabaseConnectorJdbcConnection",
@@ -783,7 +768,6 @@ connectUsingJdbcDriver <- function(jdbcDriver,
              slots = list(jConnection = "jobjRef"),
              where = class_cache)
   }
-  
   connection <- new("DatabaseConnectorJdbcConnection",
     jConnection = jConnection,
     identifierQuote = "",
@@ -796,10 +780,42 @@ connectUsingJdbcDriver <- function(jdbcDriver,
   return(connection)
 }
 
+ensureDatabaseConnectorConnectionClassExists <- function() {
+  class <- getClassDef("Microsoft SQL Server", where = class_cache, inherits = FALSE)
+  if (is.null(class) || methods::isVirtualClass(class)) {
+    setClass("Microsoft SQL Server",
+             contains = "DBIConnection",
+             where = class_cache)
+  }
+  class <- getClassDef("DatabaseConnectorConnection", where = class_cache, inherits = FALSE)
+  if (is.null(class) || methods::isVirtualClass(class)) {
+    setClass("DatabaseConnectorConnection", 
+             contains = "Microsoft SQL Server",
+             slots = list(
+               identifierQuote = "character",
+               stringQuote = "character",
+               dbms = "character",
+               uuid = "character"
+             ),
+             where = class_cache)
+  }
+}
+
 connectUsingDbi <- function(dbiConnectionDetails) {
   dbms <- dbiConnectionDetails$dbms
   dbiConnectionDetails$dbms <- NULL
   dbiConnection <- do.call(DBI::dbConnect, dbiConnectionDetails)
+  ensureDatabaseConnectorConnectionClassExists()
+  class <- getClassDef("DatabaseConnectorDbiConnection", where = class_cache, inherits = FALSE)
+  if (is.null(class) || methods::isVirtualClass(class)) {
+    setClass("DatabaseConnectorDbiConnection",
+             contains = "DatabaseConnectorConnection", 
+             slots = list(
+               dbiConnection = "DBIConnection",
+               server = "character"
+             ),
+             where = class_cache)
+  }
   connection <- new("DatabaseConnectorDbiConnection",
     server = dbms,
     dbiConnection = dbiConnection,
diff --git a/R/DBI.R b/R/DBI.R
index 95de7f29..3044c0e4 100644
--- a/R/DBI.R
+++ b/R/DBI.R
@@ -72,15 +72,6 @@ setClass("DatabaseConnectorJdbcConnection", where = class_cache)
 
 setClass("DatabaseConnectorDbiConnection", where = class_cache)
 
-
-# setClass("DatabaseConnectorDbiConnection",
-#          contains = "DatabaseConnectorConnection",
-#          slots = list(
-#            dbiConnection = "DBIConnection",
-#            server = "character"
-#          )
-# )
-
 #' Create a connection to a DBMS
 #'
 #' @description