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SQL Context

The Jinja context is available in all sql definitions such as view.sql, measure.sql, dimension.sql, and relation.sql properties. Please note that the Jinja context is different from dbt Jinja context, dbt compiles your code for once and doesn't run on-demand whereas metriql compiles Jinja variables on the fly when the user runs a query.

Benefits of using dynamic SQL contexts:

  • Using statements to control the flow of the SQL expression.
  • Accessing project and user attributes inside SQL context thus the ability to generate unique expressions.

If you want to learn more about Jinja, visit the Jinja2 documentation.

Using Jinja inside yml files

dbt compiles the resource files, so references {{TABLE}} won't work in yml files. Instead, we support {TABLE} (with one curly brace).

You can access the value of a dimension, measure, relation, or dataset target. Accessing the fields inside a SQL editor is done as follows:

Execution diagram

The context starts with model. prefix and follows the name such as app_opened. Every dataset has dimension, measure, and relation fields. You can choose to access those or just leave it as {model.app_opened} to get the SQL reference of a model.

To render a dimension, measure or relation, type a relation name followed by its name {model.app_opened.dimension._country}. The last keyword for both fields and models is optional. You can either choose to render it as projection style or filter style. The default rendering style is filter.

for datasets:#

  • {model.app_opened} > schema_name.app_opened
  • {model.app_opened.filter} > schema_name.app_opened
  • {model.app_opened} > schema_name.app_opened as app_opened

for fields:#

  • {model.app_opened.dimension._country} > schema_name.app_opened._country
  • {model.app_opened.dimension._country.filter} > schema_name.app_opened._country
  • {model.app_opened.dimension._country.projection} > schema_name.app_opened._country as _country

measures, dimensions, and relations#

When composing fields in SQL type, an additional variable is injected into the Jinja context: {TABLE}. This variable gets rendered to the model name of the field. For instance -a measure in orders model- SUM({TABLE}.price) will be rendered to SUM(orders.price).

To access other fields you can choose to access fields over a model, or the field is in the same model you access them as follows:

  • {dimension.dimension_name}
  • {measure.measure_name}
  • {relation.relation_name}

For example, composing a measure that aggregates a dimension: SUM({dimension.price}). Using this convention, the measure is rendered dynamically thus any changes to the dimension will affect how the measure is being rendered.

Other variables#

  • {TABLE}: The current datasets' name
  • {aq}: Alias quote for the target database. Ex: " for PostgreSQL and ``` for BigQuery.
  • {user}: The user attributes context.

Only available in relation.sql#

  • {TARGET}: returns the alias of the target dataset
info

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