checkpoint

docs/content/feathub-sdk/feature-view.md

@@ -38,10 +38,11 @@ A `Transformation` defines how to derive a new feature from existing features.
 FeatHub currently supports the following types of Transformations.
 
 - [ExpressionTransform](https://github.com/alibaba/feathub/blob/master/python/feathub/feature_views/transforms/expression_transform.py)
-  derives feature values by applying FeatHub expression on one row of the parent
-  table at a time. FeatHub expression language is a declarative language with
-  build-in functions. See [FeatHub expression](feathub_expression.md) for more
-  information.
+  derives feature values by applying FeatHub expression on one row of the
+  parent table at a time. The FeatHub expression language is a declarative
+  language, sharing a syntax and grammar reminiscent of the SQL SELECT clause.
+  See [here](../) for a comprehensive list of supported built-in functions and
+  operators.
 - [OverWindowTransform](https://github.com/alibaba/feathub/blob/master/python/feathub/feature_views/transforms/expression_transform.py)
   derives feature values by applying FeatHub expression and aggregation function
   on multiple rows of a table at a time.