added example on how to use the day_of_week namespace

ibis/backends/sql/compiler.py

@@ -787,7 +787,7 @@ def visit_DayOfWeekIndex(self, op, *, arg):
         return (self.f.dayofweek(arg) + 6) % 7
 
     def visit_IsoDayOfWeekIndex(self, op, *, arg):
-        return self.f.dayofweek(arg)
+        return  (self.f.dayofweek(arg) + 6) % 7+1
 
 
     def visit_DayOfWeekName(self, op, *, arg):
@@ -799,15 +799,6 @@ def visit_DayOfWeekName(self, op, *, arg):
             ifs=list(itertools.starmap(self.if_, enumerate(calendar.day_name))),
         )
 
-    def visit_DayOfWeekName(self, op, *, arg):
-        # day of week number is 0-indexed
-        # Sunday == 0
-        # Saturday == 6
-        return sge.Case(
-            this=self.f.dayofweek(arg),
-            ifs=list(itertools.starmap(self.if_, enumerate(calendar.day_name))),
-        )
-
     def visit_IntervalFromInteger(self, op, *, arg, unit):
         return sge.Interval(
             this=sge.convert(arg), unit=sge.Var(this=unit.singular.upper())

ibis/expr/operations/temporal.py

@@ -164,12 +164,23 @@ class DayOfWeekIndex(Unary):
 
     dtype = dt.int16
 
+@public
+class IsoDayOfWeekIndex(Unary):
+    arg: Value[dt.Date | dt.Timestamp]
+
+    dtype = dt.int16
+
 
 @public
 class DayOfWeekName(Unary):
     arg: Value[dt.Date | dt.Timestamp]
 
     dtype = dt.string
+@public
+class IsoDayOfWeekName(Unary):
+    arg: Value[dt.Date | dt.Timestamp]
+
+    dtype = dt.string
 
 
 @public

ibis/expr/types/temporal.py

@@ -988,3 +988,24 @@ def full_name(self):
             The name of the day of the week
         """
         return ops.DayOfWeekName(self._expr).to_expr()
+
+
+    def iso_index(self):
+        """Get the index of the day of the week in iso-format (1=Monday, 7=Sunday).
+
+        Returns
+        -------
+        IntegerValue
+            The index of the day of the week in iso-format (1=Monday, 7=Sunday).
+        """
+        return ops.IsoDayOfWeekIndex(self._expr).to_expr()
+
+    def iso_full_name(self):
+        """Get the name of the day of the week.
+
+        Returns
+        -------
+        StringValue
+            The name of the day of the week
+        """
+        return ops.IsoDayOfWeekName(self._expr).to_expr()