diff --git a/distribution/lib/Standard/Database/0.0.0-dev/src/Internal/SQLite/SQLite_Type_Mapping.enso b/distribution/lib/Standard/Database/0.0.0-dev/src/Internal/SQLite/SQLite_Type_Mapping.enso
index 64fd06a2808ff..026672cea019d 100644
--- a/distribution/lib/Standard/Database/0.0.0-dev/src/Internal/SQLite/SQLite_Type_Mapping.enso
+++ b/distribution/lib/Standard/Database/0.0.0-dev/src/Internal/SQLite/SQLite_Type_Mapping.enso
@@ -5,6 +5,7 @@ import Standard.Base.Errors.Illegal_State.Illegal_State
 import Standard.Table.Data.Type.Enso_Types
 import Standard.Table.Data.Type.Value_Type.Value_Type
 import Standard.Table.Data.Type.Value_Type.Bits
+import Standard.Table.Data.Type.Value_Type_Helpers
 from Standard.Table.Errors import Inexact_Type_Coercion
 
 import project.Data.Column.Column
@@ -118,7 +119,11 @@ type SQLite_Type_Mapping
                 Panic.throw (Illegal_State.Error "Impossible: IIF must have 3 arguments. This is a bug in the Database library.")
             inputs_types = arguments.drop 1 . map find_type
             if inputs_types.first == inputs_types.second then return inputs_types.first else
-                infer_default_type
+                case Value_Type_Helpers.reconcile_types inputs_types.first inputs_types.second of
+                    ## Inference failed, fall back to default type.
+                       Ideally, should never happen. To be handled in #6106.
+                    Value_Type.Mixed -> infer_default_type
+                    common -> return common
 
         always_boolean_ops = ["==", "!=", "equals_ignore_case", ">=", "<=", "<", ">", "BETWEEN", "AND", "OR", "NOT", "IS_NULL", "IS_NAN", "IS_EMPTY", "LIKE", "IS_IN", "starts_with", "ends_with", "contains"]
         always_text_ops = ["ADD_TEXT", "CONCAT", "CONCAT_QUOTE_IF_NEEDED"]
diff --git a/test/Table_Tests/src/Common_Table_Operations/Column_Operations_Spec.enso b/test/Table_Tests/src/Common_Table_Operations/Column_Operations_Spec.enso
index d82288156d2fa..86ec7e2263b25 100644
--- a/test/Table_Tests/src/Common_Table_Operations/Column_Operations_Spec.enso
+++ b/test/Table_Tests/src/Common_Table_Operations/Column_Operations_Spec.enso
@@ -19,7 +19,11 @@ spec setup =
             t = table_builder [["X", [True, False, Nothing, True]]]
             t.at "X" . iif 22 33 . to_vector . should_equal [22, 33, Nothing, 22]
 
-        Test.specify "iif on Columns" pending="Not implemented yet." Nothing
+        Test.specify "iif on Columns" <|
+            t = table_builder [["X", [True, False, Nothing, False]], ["Y", [1, 2, 3, 4]], ["Z", [1.5, 2.5, 3.5, 4.5]]]
+            c = t.at "X" . iif (t.at "Y") (t.at "Z")
+            c.value_type . is_floating_point . should_be_true
+            c.to_vector . should_equal [1, 2.5, Nothing, 4.5]
 
     t2 = table_builder [["x", [1, 4, 5, Nothing]], ["y", [2, 3, 5, Nothing]], ["b", [False, False, True, Nothing]]]
     x = t2.at "x"