DBT DBT Sources & Seeds

Question 1

In dbt, what is a 'source' used for?

Accepted Answer

Declaring raw database tables that dbt did not create

Answer

Sources let you declare raw tables loaded by external tools so dbt can reference, document, and test them.

Question 2

Which dbt function is used to reference a source table inside a model SQL file?

Accepted Answer

Answer

The `{{ source('source_name', 'table_name') }}` function resolves to the fully qualified table path defined in sources.yml.

Question 3

What dbt command checks whether source tables are fresh based on a loaded_at_field?

Accepted Answer

dbt source freshness

Answer

`dbt source freshness` queries the `loaded_at_field` of each source and compares it against the defined freshness thresholds.

Question 4

Which YAML key defines how old source data can be before dbt warns about staleness?

Accepted Answer

freshness

Answer

The `freshness:` block under a source (or table) defines `warn_after` and `error_after` thresholds for data staleness.

Question 5

What is a dbt seed?

Accepted Answer

A CSV file loaded into the warehouse as a table

Answer

Seeds are CSV files in the `seeds/` directory that `dbt seed` loads into database tables, useful for static lookup data.

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