Adding logic to unpivot to handle boolean columns.

README.md

@@ -556,6 +556,7 @@ Arguments:
 
 #### unpivot ([source](macros/sql/unpivot.sql))
 This macro "un-pivots" a table from wide format to long format. Functionality is similar to pandas [melt](http://pandas.pydata.org/pandas-docs/stable/generated/pandas.melt.html) function.
+Boolean values are replaced with the strings 'true'|'false'
 
 Usage:
 ```

integration_tests/data/sql/data_unpivot_bool.csv

@@ -0,0 +1,4 @@
+customer_id,created_at,status,segment,is_updated
+123,2017-01-01,active,tier 1,TRUE
+234,2017-02-01,active,tier 3,FALSE
+567,2017-03-01,churned,tier 2,TRUE

integration_tests/data/sql/data_unpivot_bool_expected.csv

@@ -0,0 +1,10 @@
+customer_id,created_at,prop,val
+123,"2017-01-01","segment","tier 1"
+123,"2017-01-01","status","active"
+123,"2017-01-01","is_updated","true"
+234,"2017-02-01","segment","tier 3"
+234,"2017-02-01","status","active"
+234,"2017-02-01","is_updated","false"
+567,"2017-03-01","status","churned"
+567,"2017-03-01","is_updated","true"
+567,"2017-03-01","segment","tier 2"

integration_tests/models/sql/schema.yml

@@ -96,6 +96,11 @@ models:
  - dbt_utils.equality:
  compare_model: ref('data_unpivot_expected')
 
+ - name: test_unpivot_bool
+ tests:
+ - dbt_utils.equality:
+ compare_model: ref('data_unpivot_bool_expected')
+
  - name: test_star
  tests:
  - dbt_utils.equality:

integration_tests/models/sql/test_unpivot_bool.sql

@@ -0,0 +1,32 @@
+
+-- snowflake messes with these tests pretty badly since the
+-- output of the macro considers the casing of the source
+-- table columns. Using some hacks here to get this to work,
+-- but we should consider lowercasing the unpivot macro output
+-- at some point in the future for consistency
+
+{% if target.name == 'snowflake' %}
+ {% set exclude = ['CUSTOMER_ID', 'CREATED_AT'] %}
+{% else %}
+ {% set exclude = ['customer_id', 'created_at'] %}
+{% endif %}
+
+
+select
+ customer_id,
+ created_at,
+ case
+ when '{{ target.name }}' = 'snowflake' then lower(prop)
+ else prop
+ end as prop,
+ val
+
+from (
+ {{ dbt_utils.unpivot(
+ relation=ref('data_unpivot_bool'),
+ cast_to=dbt_utils.type_string(),
+ exclude=exclude,
+ field_name='prop',
+ value_name='val'
+ ) }}
+) as sbq

macros/sql/unpivot.sql

@@ -52,7 +52,12 @@ Arguments:
  {%- endfor %}
 
  cast('{{ col.column }}' as {{ dbt_utils.type_string() }}) as {{ field_name }},
- cast({{ col.column }} as {{ cast_to }}) as {{ value_name }}
+ cast( {% if col.data_type == 'boolean' %}
+ case when {{ col.column }} then 'true' else 'false' end
+ {% else %}
+ {{ col.column }}
+ {% endif %}
+ as {{ cast_to }}) as {{ value_name }}
 
  from {{ relation }}