diff --git a/pyproject.toml b/pyproject.toml
index 0f09087..374d0fa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "rda_python_common"
-version = "2.0.20"
+version = "2.1.1"
 authors = [
   { name="Zaihua Ji", email="zji@ucar.edu" },
 ]
diff --git a/src/rda_python_common/pg_dbi.py b/src/rda_python_common/pg_dbi.py
index e89a606..89bb495 100644
--- a/src/rda_python_common/pg_dbi.py
+++ b/src/rda_python_common/pg_dbi.py
@@ -20,17 +20,18 @@
 from .pg_log import PgLOG
 
 class PgDBI(PgLOG):
-   
-   #  PostgreSQL specified query timestamp format
-   fmtyr = lambda fn: "extract(year from {})::int".format(fn)
-   fmtqt = lambda fn: "extract(quarter from {})::int".format(fn)
-   fmtmn = lambda fn: "extract(month from {})::int".format(fn)
-   fmtdt = lambda fn: "date({})".format(fn)
-   fmtym = lambda fn: "to_char({}, 'yyyy-mm')".format(fn)
-   fmthr = lambda fn: "extract(hour from {})::int".format(fn)
 
    def __init__(self):
       super().__init__()  # initialize parent class
+
+      #  PostgreSQL specified query timestamp format
+      self.fmtyr = lambda fn=self: "extract(year from {})::int".format(fn)
+      self.fmtqt = lambda fn=self: "extract(quarter from {})::int".format(fn)
+      self.fmtmn = lambda fn=self: "extract(month from {})::int".format(fn)
+      self.fmtdt = lambda fn=self: "date({})".format(fn)
+      self.fmtym = lambda fn=self: "to_char({}, 'yyyy-mm')".format(fn)
+      self.fmthr = lambda fn=self: "extract(hour from {})::int".format(fn)
+
       self.pgdb = None    # reference to a connected database object
       self.curtran = 0    # 0 - no transaction, 1 - in transaction
       self.NMISSES = []   # array of mising userno