Databases and warehouses
Find and export
your BigQuery data.
BigQuery reports logical and physical bytes separately. Use one clearly named basis for the inventory, with dataset locations and retained snapshots identified.
- Report in
- GB
- Category
- Databases and warehouses
- Last checked
Find your BigQuery data size
- Use the required metadata access in each project.
- Review INFORMATION_SCHEMA.TABLE_STORAGE for each dataset region, or a table's Details → Storage info.
- Record logical bytes and physical bytes separately rather than adding them.
- Inspect row quantities and the earliest relevant business timestamps across the tables in scope.
What to include in your data inventory
Report in GB, stating logical or physical storage and the projects, datasets and regions included.
Give table and row quantities where available, the earliest event dates, and whether snapshots or historical retention are included.
Export your BigQuery history
- Have the administrator confirm table-export and job permissions plus access to an approved Cloud Storage destination.
- For each table, use Export / sync → Cloud Storage, bq extract or SQL EXPORT DATA.
- Choose Parquet, Avro or another suitable format; use a wildcard destination for output split across files.
- Collect all shards and preserve the schema and table identity.
CSV cannot represent nested and repeated fields in the same way as richer structured formats. Choose the format according to the schema.
Exports can incur processing or storage costs under the selected method. Review table size and applicable quotas before a large collection.
Why BigQuery data has value for AI training
Warehouse tables can connect events across a company's applications and reporting systems.
Dataset descriptions and relationships help explain what an event represents and how it links to later outcomes.
What stays private
Select projects, datasets and columns in scope, reviewing personal data and unrelated analytical workloads.
Telegraph Lab reviews the proposed material with you and agrees how sensitive information will be handled. Preparation can include excluding material, redacting details and replacing personal identifiers. Your company keeps ownership; the licensing agreement defines the material, permitted uses and authorized recipients.
Common questions about BigQuery data
Should logical and physical GB be added?
They describe different representations. Report them separately and identify the basis.
Why query each region?
Storage metadata is location-scoped. Run the appropriate query for each dataset location.
Can every table use CSV?
Nested and repeated fields need a suitable supported format such as Parquet, Avro or JSON.
Why are there many output files?
Large exports are split into shards. Keep all files and their table identity together.