Assertion

Class: Assertion

An assertion is a data quality test query that finds rows that violate one or more conditions specified in the query. If the query returns any rows, the assertion fails.

You can create assertions in the following ways. Available config options are defined in AssertionConfig, and are shared across all the following ways of creating assertions.

Using a SQLX file:

-- definitions/name.sqlx
config {
  type: "assertion"
}
SELECT * FROM table WHERE a IS NULL

Using built-in assertions in the config block of a table:

See TableConfig.assertions

Using action configs files:

definitions/actions.yaml

actions:
- assertion:
  filename: name.sql

-- definitions/name.sql
SELECT * FROM table WHERE a IS NULL

Using the Javascript API:

definitions/file.js

assert("name").query("SELECT * FROM table WHERE a IS NULL")

Note: When using the Javascript API, methods in this class can be accessed by the returned value. This is where query comes from.

Naming the assertion:

By default an assertion is named after its file: definitions/name.sqlx creates an assertion called name in your assertion schema. Set name in the config to override that. Other actions then refer to it by the new name, for example in dependencies:

-- definitions/checks/nulls.sqlx
config {
  type: "assertion",
  name: "orders_no_null_ids"
}
SELECT * FROM table WHERE a IS NULL

name works the same way next to filename in an action configs file. In the Javascript API the name is the first argument.

Hierarchy

• ActionBuilder‹Assertion›

  ↳ Assertion

Index

Methods

• database
• dependencies
• description
• disabled
• hermetic
• query
• schema
• tags

Methods

database

▸ database(database: string): this

deprecated Deprecated in favor of AssertionConfig.project.

Sets the database in which to create the corresponding view for this assertion. For BigQuery targets this is the Google Cloud project ID; for Postgres/Supabase targets this is the database name configured in workflow_settings.yaml.

Parameters:

Name	Type
database	string

Returns: this

---

dependencies

▸ dependencies(value: Resolvable | Resolvable[]): this

deprecated Deprecated in favor of AssertionConfig.dependencies.

Sets dependencies of the assertion.

Parameters:

Name	Type
value	Resolvable | Resolvable[]

Returns: this

---

description

▸ description(description: string): this

deprecated Deprecated in favor of AssertionConfig.description.

Sets the description of this assertion.

Parameters:

Name	Type
description	string

Returns: this

---

disabled

▸ disabled(disabled: boolean): this

deprecated Deprecated in favor of AssertionConfig.disabled.

If called with true, this action is not executed. The action can still be depended upon. Useful for temporarily turning off broken actions.

Parameters:

Name	Type	Default
disabled	boolean	true

Returns: this

---

hermetic

▸ hermetic(hermetic: boolean): void

deprecated Deprecated in favor of AssertionConfig.hermetic.

If true, this indicates that the action only depends on data from explicitly-declared dependencies. Otherwise if false, it indicates that the action depends on data from a source which has not been declared as a dependency.

Parameters:

Name	Type
hermetic	boolean

Returns: void

---

query

▸ query(query: AContextable‹string›): this

Sets the query to be run by the assertion.

Parameters:

Name	Type
query	AContextable‹string›

Returns: this

---

schema

▸ schema(schema: string): this

deprecated Deprecated in favor of AssertionConfig.dataset.

Sets the schema in which to create the corresponding view for this assertion. For BigQuery targets this is the dataset name; for Postgres/Supabase targets this is the schema name (e.g. public).

Parameters:

Name	Type
schema	string

Returns: this

---

tags

▸ tags(value: string | string[]): this

deprecated Deprecated in favor of AssertionConfig.tags.

Sets a list of user-defined tags applied to this action.

Parameters:

Name	Type
value	string | string[]

Returns: this