Specifies whether STRUCT fields in Google BigQuery are flattened into individual top-level columns.

Data Type

bool

Default Value

true

Remarks

When set to true, the server flattens each field in a STRUCT column into its own column. The original STRUCT column is omitted from the results. This flattening is applied recursively for nested STRUCT fields.

For example, the following table is reported as three columns when flattening is enabled: location.coords.lat, location.coords.lon, and location.country

CREATE TABLE t(location STRUCT<coords STRUCT<lat FLOAT64, lon FLOAT644>, country STRING4>);

When set to false, the server returns the STRUCT column as a single column containing a JSON object. In the example above, only the location column is reported.

Enable this property to access nested STRUCT fields as individual columns. Disable it if your application prefers to handle STRUCTs as JSON values.