Merge pull request dbt-labs#100 from fishtown-analytics/feature/lengt…

…h-macro

Feature: length macro

integration_tests/data/cross_db/data_length.csv

@@ -0,0 +1,5 @@
+expression,output
+abcdef,6
+fishtown,8
+december,8
+www.google.com/path,19

integration_tests/models/cross_db_utils/schema.yml

@@ -42,6 +42,12 @@ models:
       - assert_equal:
           actual: actual
           expected: expected
+
+  - name: test_length
+    tests:
+      - assert_equal:
+          actual: actual
+          expected: expected
 
   - name: test_safe_cast
     tests:

integration_tests/models/cross_db_utils/test_length.sql

@@ -0,0 +1,12 @@
+with data as (
+
+    select * from {{ ref('data_length') }}
+
+)
+
+select
+
+    {{ dbt_utils.length('expression') }} as actual,
+    output as expected
+
+from data

macros/cross_db_utils/length.sql

@@ -0,0 +1,21 @@
+{% macro length(expression) -%}
+    {{ adapter_macro('dbt_utils.length', expression) }}
+{% endmacro %}
+
+
+{% macro default__length(expression) %}
+
+    length(
+        {{ expression }}
+    )
+
+{%- endmacro -%}
+
+
+{% macro redshift__length(expression) %}
+
+    len(
+        {{ expression }}
+    )
+
+{%- endmacro -%}