This determines what percent of a table is sampled with the TABLESAMPLE operator.

Data Type

string

Default Value

""

Remarks

This option can be set to make the driver use the TABLESAMPLE for each table referenced by a query. The value determines what percent is provided to the PERCENT clause. That clause will only be generated if this property's value is above zero.

-- Input SQL
SELECT * FROM `tbl`

-- Generated Google BigQuery SQL when TableSamplePercent=10
SELECT * FROM `tbl` TABLESAMPLE SYSTEM (10 PERCENT)

This option is subject to a few limitations:

• It is applied during query converison and has no effect when QueryPassthrough is set.
• More rows may be returned than expected due to how the server implements TABLESAMPLE. Please see the Google BigQuery documentation for more information.
• TABLESAMPLE is not supported on views. If a view is queried in sampling mode, the driver will omit the TABLESAMPLE clause for the view.