Data Warehouse Engineer Interview Questions and Answers

A pre hook in dbt is a script that runs before a model is built, allowing for custom actions or transformations.

• Pre hooks can be used to clean or preprocess data before loading it into a model

• They are defined in the dbt project YAML file for a specific model

• Examples of pre hooks include data validation checks, data type conversions, or data filtering

dbt materialisations are pre-aggregated tables or views created to improve query performance in data warehouses.

• Materialisations are created using dbt models with the 'materialized' parameter set to 'table' or 'view'.

• They can be used to store intermediate results of complex queries to avoid recalculating them every time.

• Materialisations can improve query performance by reducing the amount of data that needs to be processed.

• Examples of materialisations include summary tables, ...read more