The purpose of the dq tool is to make simple storing test results and visualisation of these in a BI dashboard.
Supported DWHs:
Installation:
-
Add to
packages.yml
file:packages: - package: infinitelambda/dq_tools version: [">=1.8.0", "<1.9.0"]
-
(Optional) Configure schema in
dbt_project.yml
file:models: dq_tools: # +database: DQ +schema: AUDIT vars: # (TO BE DEPRECATED, currently used only in test macros) # dbt_dq_tool_database: DQ dbt_dq_tool_schema: AUDIT
-
Add on-run-end hook:
on-run-end: - '{{ dq_tools.store_test_results(results) }}'
-
Initialize
dq-tools
(new in v1.4+)dbt run -s dq_tools
-
Then, decide to save the test result in dbt command:
dbt test --vars '{dq_tools_enable_store_test_results: True}' dbt build --vars '{dq_tools_enable_store_test_results: True}'
Alternatively, we can also enable this variable in
dbt_project.yml`
:vars: # to store the test results in db table dq_tools_enable_store_test_results: True
See Installation Instructions in more details.
- store dbt test results in a table
- create mart for DQ test result
- provide BI dashboard for visualisation
The idea behind the layer is that each layer can be changed, extended or replaced without or with minimal impact on the other 2.
There are 6 main KPIs will be produced as below:
- Accuracy
- Consistency
- Completeness
- Timeliness
- Validity
- Uniqueness
NOTE: It is possible that we can have custom KPI(s) as you go but it is NOT recommended as the existing modelling design will stick to the above 6 ones only.
models:
- name: my_model
columns:
- name: my_column
data_tests:
- dq_tools.unique_where_db:
kpi_category: MyKPI # not recommended
-
STEP 1 - Installation:
- install dq tools package
- create dq log issue table following the documentation in the package.
- create metrics views
- set up looker dashboard
-
STEP 2 - define dbt data_tests: Define tests following the description in the package documentation.
models: - name: dim_customers description: This table has basic information about a customer, as well as some derived facts based on a customer's orders data_tests: - dq_tools.equal_rowcount_where_db: compare_model: ref('stg_customers') where: customer_id > 50 compare_model_where: customer_id > 50 columns: - name: customer_id description: This is a unique identifier for a customer data_tests: - dq_tools.unique_where_db - dq_tools.not_null_where_db
-
STEP 3 - run the dbt test and check: Test results in the dq issue log table:
Go to dbt Hub and register the package into your dbt packages.yml
file:
packages:
- package: infinitelambda/dq_tools
version: [">=1.2.0", "<1.3.0"]
Since the version 1.3, the table dq_issue_log
is made as dbt model, no more manual hook config 🎉.
It should be created automatically within your upstream dbt command. If not, all you should do that is running the command: dbt run -s dq_tools
.
Note
If you already have a metricflow_time_spine
model in your project, you will encounter a Compilation error when executing dbt run -s dq_tools
. In this scenario, disable the metricflow_time_spine
model by updating its configuration in your project (path: your_project/dbt_packages/dq_tools/models/04_metric/metricflow_time_spine).
For dq-tools legacy version >=1.0,<1.3
A macro create_table_dq_issue_log
(source) will create the log table in your database (Snowflake) / project (BigQuery).
Add on-run-start
hook (required dbt >= 1.0.0):
on-run-start:
- '{{ dq_tools.create_table_dq_issue_log() }}'
For dq-tools legacy version < 1.0, you can run it as an operation
dbt run-operation create_dq_issue_log
Value for variable dbt_dq_tool_schema: your_schema_name
needs to be added to dbt_project.yml file in your project. And then, optionally add dbt_dq_tool_database: your_database_name
which default value is target.schema
in profiles.yml
file
e.g.
vars:
# (optional) to create db table in the schema named as AUDIT, default to `target.schema`
dbt_dq_tool_schema: AUDIT
# (optional) to create db table in the database named as DQ_TOOLS, default to `target.database`
dbt_dq_tool_database: DQ_TOOLS
Add the on-run-end
hook to you project:
on-run-end:
- '{{ dq_tools.store_test_results(results) }}'
Then, decide to save the test result in dbt command:
dbt test --vars '{dq_tools_enable_store_test_results: True}'
dbt build --vars '{dq_tools_enable_store_test_results: True}'
Alternatively, we can also enable this variable in dbt_project.yml`
:
vars:
# to store the test results in db table
dq_tools_enable_store_test_results: True
Pros & Cons:
- Pros:
- Save both type of tests (singular and generic) result to log table
- Save test result from any test functions (outside of dq-tools ones)
- Cons
- Only availabe on the latest version
- Singular Test: table_name / ref_table: cannot be captured
- Singular Test: no_of_records cannot be captured
For dq_tools version < 1.0 (with legacy variable)
Optionally, add dbt_test_results_to_db: False
as a variable to your dbt_profile.yml
file. Its default value is False
meaning NOT to save test result.
e.g.
vars:
# to store the test results in db table
dbt_test_results_to_db: False
You can also specify the variable in dbt commands e.g.
dbt test -s your_model vars '{dbt_test_results_to_db: True}'
dbt build -s your_model vars '{dbt_test_results_to_db: True}'
Additionally, you MUST know that when you generate the doc or compile the code, this variable dbt_test_results_to_db
is super important. If it's defined as True
, it will run the test when generating the documentation or compiling. (indeed generating the doc compile the code first see: Generating project documentation).
So you should either pass the variable when generating the doc and compiling the code.
dbt docs generate --vars 'dbt_test_results_to_db: False'
dbt compile --vars 'dbt_test_results_to_db: False'
Either defined it to false in the default variables and defined the variables when running the test.
dbt test --vars 'dbt_test_results_to_db: False'
Pros & Cons:
-
Pros:
- Automatically save generic test result (if you used dq-tools functions)
-
Cons:
- Requires to create new test function(s) in advanced case(s) to adapt with current implementation of test result capturing approach
- Singular test functions is not documented (?)
Since the version 1.4+, all models and metrics will be enabled by default.
For dq-tools version <1.4
Enable it in dbt_project.yml
file:
# dbt_project.yml
models:
dq_tools:
+enabled: true
metrics:
dq_tools:
+enabled: true
store_test_results (source)
This macro is used to parse results
variable at the on-run-end
context to achieve the test result nodes, and save them to the DQ_ISSUE_LOG
table.
If the model is materialized as ephemeral
, this macro will insert the null value for aggregated fields related to tested model.
Usage:
# dbt_project.yml
on-run-end:
- '{{ dq_tools.store_test_results(results) }}'
Besides, there are couple of private macros are used as a part of it aiming to extract/calculate things under (here)
These tests are based on dbt_utils test. The test result will be stored in a database table and further analysis can be built on these.
Detailed informations will be stored such as check_timestamp, table_name, column_name, value, severity, no_of records etc.
not_null_where_db (source)
This test validates that there are no null values present in a column for a subset of rows by specifying a where
clause.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Completeness.
Usage:
version: 2
models:
- name: my_model
columns:
- name: id
data_tests:
- dq_tools.not_null_where_db:
where: "_deleted = false"
severity_level: error
kpi_category: Completeness
relationships_where_db (source)
This test validates the referential integrity between two relations (same as the core relationships schema test) with an added predicate to 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.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Consistency.
Usage:
version: 2
models:
- name: model_name
columns:
- name: id
data_tests:
- dq_tools.relationships_where_db:
to: ref('other_model_name')
field: client_id
from_condition: id <> '4ca448b8-24bf-4b88-96c6-b1609499c38b'
severity_level: warn
kpi_category: Consistency
unique_where_db (source)
This test validates that there are no duplicate values present in a field for a subset of rows by specifying a where
clause.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Uniqueness.
Usage:
version: 2
models:
- name: my_model
columns:
- name: id
data_tests:
- dq_tools.unique_where_db:
where: "_deleted = false"
severity_level: error
kpi_category: Uniqueness
recency_db (source)
This schema test asserts that there is data in the referenced model at least as recent as the defined interval prior to the current timestamp.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Timeliness.
Usage:
version: 2
models:
- name: model_name
data_tests:
- dq_tools.recency_db:
datepart: day
field: created_at
interval: 1
severity_level: warn
kpi_category: Timeliness
expression_is_true_db (source)
This schema test asserts that a valid sql expression is true for all records. This is useful when checking integrity across columns, for example, that a total is equal to the sum of its parts, or that at least one column is true.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Validity.
Usage:
version: 2
models:
- name: model_name
data_tests:
- dq_tools.expression_is_true_db:
expression: "col_a + col_b = total"
kpi_category: Validity
accepted_values_where_db (source)
This schema test asserts that all of the column values are within the list of accepted values provided. As with other schema tests, optional parameter where
can be specified for testing just a subset of the column.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Accuracy.
Usage:
version: 2
models:
- name: model_name
data_tests:
- dq_tools.accepted_values_where_db:
values: [value1, value2]
severity_level: warn
kpi_category: Accuracy
equal_rowcount_where_db (source)
This schema test asserts that count of rows in two relations is the same. Optional parameters where
and compare_model_where
can be specified for testing just a subset of base and compared relations respectively.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Consistency.
Usage:
version: 2
models:
- name: model_name
data_tests:
- dq_tools.equal_rowcount_where_db:
compare_model: some_other_model
where: "_deleted = false"
compare_model_where: "_deleted = false"
severity_level: warn
equality_where_db (source)
This schema test asserts that two relations (or subset of their columns) are equal. Relations as a whole are considered if the parameter compare_columns
is not provided.
Optional parameters where
and compare_model_where
can be specified for testing just a subset of base and compared relations respectively.
All data quality issues are stored in the dq_issues_log table.
If not specified the default severity level is 'warn'. This option coresponds with dbts severity setting.
Kpi_category option allows you to change the default category, which this test will fall into in the looker dq_mart dashboard. Accepted values are: [Accuracy
, Consistency
, Completeness
, Timeliness
, Validity
, Uniqueness
]. Any other value will fall into Other
. Default option for this test is Consistency.
Usage:
version: 2
models:
- name: model_name
data_tests:
- dq_tools.equality_where_db:
compare_model: some_other_model
compare_columns:
- column1
- column2
where: "_deleted = false"
compare_model_where: "_deleted = false"
severity_level: warn
If you've ever wanted to contribute to this tool, and a great cause, feel free to create your Pull Request, or submit a new issue via Bug Report / Feature Request 💖