diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..5b6a065
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+.Rproj.user
+.Rhistory
+.RData
+.Ruserdata
diff --git a/RPostgreSQL/.gitignore b/RPostgreSQL/.gitignore
new file mode 100644
index 0000000..2f5308e
--- /dev/null
+++ b/RPostgreSQL/.gitignore
@@ -0,0 +1,3 @@
+*.log
+*.status
+*.dSYM
diff --git a/RPostgreSQL/R/PostgreSQL.R b/RPostgreSQL/R/PostgreSQL.R
index 8db97c9..8b255e5 100644
--- a/RPostgreSQL/R/PostgreSQL.R
+++ b/RPostgreSQL/R/PostgreSQL.R
@@ -73,6 +73,11 @@ setMethod("dbConnect", "character",
           valueClass = "PostgreSQLConnection"
           )
 
+setMethod("dbIsValid", "PostgreSQLConnection", 
+          def = function(dbObj, ... ) isPostgresqlIdCurrent(dbObj, ... ),
+          valueClass = "logical"
+)
+
 ## clone a connection
 setMethod("dbConnect", "PostgreSQLConnection",
           def = function(drv, ...) postgresqlCloneConnection(drv, ...),
@@ -234,6 +239,7 @@ setMethod("dbListFields",
               flds <- dbGetQuery(conn,
                   paste("select a.attname from pg_attribute a, pg_class c, pg_tables t, pg_namespace nsp",
                   " where a.attrelid = c.oid and c.relname = tablename and c.relnamespace = nsp.oid and a.attnum > 0 and ",
+                  "not a.attisdropped and ",
                   "nspname = current_schema() and schemaname = nspname and ",
                   "tablename = '", postgresqlEscapeStrings(conn, name), "'", sep=""))[,1]
               }
@@ -242,6 +248,7 @@ setMethod("dbListFields",
                   flds <- dbGetQuery(conn,
                       paste("select a.attname from pg_attribute a, pg_class c, pg_tables t, pg_namespace nsp",
                       " where a.attrelid = c.oid and c.relname = t.tablename and c.relnamespace = nsp.oid and a.attnum > 0 and ",
+                      "not a.attisdropped and ",
                       "nspname = schemaname ",
                       "and schemaname = '", postgresqlEscapeStrings(conn, name[1]), "' ",
                       "and tablename = '", postgresqlEscapeStrings(conn, name[2]), "'", sep=""))[,1]
diff --git a/RPostgreSQL/R/dbObjectId.R b/RPostgreSQL/R/dbObjectId.R
index abf51eb..d8e285e 100644
--- a/RPostgreSQL/R/dbObjectId.R
+++ b/RPostgreSQL/R/dbObjectId.R
@@ -51,6 +51,7 @@ setMethod("print", "dbObjectId",
 
 ## verify that obj refers to a currently open/loaded database
 isPostgresqlIdCurrent <- function(obj) {
+    if(is.null(obj)) return(FALSE)
     obj <- as(obj, "integer")
     .Call(RS_DBI_validHandle, obj)
 }
diff --git a/RPostgreSQL/src/.gitignore b/RPostgreSQL/src/.gitignore
new file mode 100644
index 0000000..aad4fde
--- /dev/null
+++ b/RPostgreSQL/src/.gitignore
@@ -0,0 +1,3 @@
+*.so
+*.o
+Makevars