BigQuery - Select Top N Records

Raymond Tang Raymond Tang 0 44996 28.66 index 3/11/2021

In BigQuery, there is no TOP N clause implemented however there is LIMIT clause available.

LIMIT clause

The following query retrieves 10 records from table table_nameof data set data_setin projectproject_test.

select * from  `project_test.data_set.table_name` limit 10;

Cost implications

warning LIMIT clause doesn't reduce cost! Please add necessary filters and only query the required columns to reduce cost.

It's very important to understand that LIMIT doesn't reduce your query cost. In the above example, all the records in the table will be read and then only 10 will be returned.  Thus please take this into consideration.

Preview feature

If the purpose is to inspect the sample data in the table, please use preview feature of BigQuery which is free.

Follow these steps to do that:

  • Expand your BigQuery project and data set.
  • Select the table you'd like to inspect.
  • In the opened tab, click Preview.

Preview will show the sample data in the table.

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bigquery gcp

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