Add model conditions to equality test

README.md

@@ -114,7 +114,7 @@ This test supports the `group_by_columns` parameter; see [Grouping in tests](#gr
 
 ### equality ([source](macros/generic_tests/equality.sql))
 
-Asserts the equality of two relations. Optionally specify a subset of columns to compare or exclude, and a precision to compare numeric columns on.
+Asserts the equality of two relations. Optionally specify a subset of columns to compare or exclude, and a precision to compare numeric columns on. An optional predicate can filter out some rows from the test. This is useful to exclude records such as test entities, rows created in the last X minutes/hours to account for temporary gaps due to ETL limitations, etc.
 
 **Usage:**
 
@@ -145,6 +145,16 @@ models:
           compare_model: ref('other_table_name')
           exclude_columns:
             - third_column
+
+  # only compare some rows in model_name or other_table_name
+  - name: model_name
+    tests:
+      - dbt_utils.equality:
+          compare_model: ref('other_table_name')
+          # Exclude rows from model_name with given identifier
+          model_condition: id <> '4ca448b8-24bf-4b88-96c6-b1609499c38b'
+          # Exclude rows from other_table_name newer than the given date
+          compare_model_condition: updated_date < '2020-01-01'
 ```
 
 ### expression_is_true ([source](macros/generic_tests/expression_is_true.sql))

integration_tests/data/schema_tests/data_test_equality_condition_a.csv

@@ -0,0 +1,5 @@
+col_a,col_b,col_c
+1,1,3
+1,2,1
+2,3,3
+4,5,6

integration_tests/data/schema_tests/data_test_equality_condition_b.csv

@@ -0,0 +1,5 @@
+col_a,col_b,col_c
+1,1,3
+1,2,1
+2,3,3
+5,6,7

integration_tests/models/generic_tests/schema.yml

@@ -164,6 +164,13 @@ seeds:
           exclude_columns:
             - col_c
 
+  - name: data_test_equality_condition_a
+    data_tests:
+      - dbt_utils.equality:
+          compare_model: ref('data_test_equality_condition_b')
+          model_condition: col_a <> 4
+          compare_model_condition: col_a <> 5
+
   - name: data_test_equality_floats_a
     data_tests:
       # test precision only

macros/generic_tests/equality.sql

@@ -1,8 +1,11 @@
-{% test equality(model, compare_model, compare_columns=None, exclude_columns=None, precision = None) %}
-  {{ return(adapter.dispatch('test_equality', 'dbt_utils')(model, compare_model, compare_columns, exclude_columns, precision)) }}
+{% test equality(model, compare_model, compare_columns=None, exclude_columns=None, precision = None, model_condition="1=1", compare_model_condition="1=1") %}
+  {{ return(adapter.dispatch('test_equality', 'dbt_utils')(model, compare_model, compare_columns, exclude_columns, precision, model_condition, compare_model_condition)) }}
 {% endtest %}
 
-{% macro default__test_equality(model, compare_model, compare_columns=None, exclude_columns=None, precision = None) %}
+{% macro default__test_equality(model, compare_model, compare_columns=None, exclude_columns=None, precision = None, model_condition="1=1", compare_model_condition="1=1") %}
+
+{# T-SQL has no boolean data type so we use 1=1 which returns TRUE #}
+{# ref https://stackoverflow.com/a/7170753/3842610 #}
 
 {%- if compare_columns and exclude_columns -%}
     {{ exceptions.raise_compiler_error("Both a compare and an ignore list were provided to the `equality` macro. Only one is allowed") }}
@@ -129,12 +132,16 @@ with a as (
 
     select * from {{ model }}
 
+    where {{ model_condition }}
+
 ),
 
 b as (
 
     select * from {{ compare_model }}
 
+    where {{ compare_model_condition }}
+
 ),
 
 a_minus_b as (