BigQuery Data Type Conversions

NOTE: The Cloud Dataprep data types listed in this page reflect the raw data type of the converted column. Depending on the contents of the column, the Transformer Page may re-infer a different data type, when a dataset using this type of source is loaded.

Access/Read

When a BigQuery data type is imported, its data type is remapped according to the following table.

Tip: Data precision may be lost during conversion. You may want to generate min and max values and compute significant digits for values in your BigQuery tables and then compute the same in Cloud Dataprep by TRIFACTA INC..

Source Data TypeSupported?

Cloud Dataprep Data Type

Notes
StringYString
BytesYString
IntegerYInteger
FloatYDecimal
BooleanYBoolean
TimestampYDatetimeMillisecond and microsecond precision in BigQuery is dropped during the import process.
DateYDatetime

If imported data contains microsecond precision, values are handled differently depending on the area of the product:

  • Initial sampling, import: Uses the BigQuery API, which can return microseconds.
  • All other areas of the product, including job execution: Uses the Cloud Dataflow SDK, which returns milliseconds.
TimeYDatetime
DatetimeYDatetime
ArrayYArray
RecordYObject

Publish/Write

NOTE: Cloud Dataprep data types not listed here are written as string types in the target database.

Cloud Dataprep Data Type BigQuery Data TypeNotes
StringString
IntegerInteger
DecimalFloat
BooleanBoolean
DatetimeDatetimeTarget data type is based on the underlying data. Time zone information is lost.
Datetime (time data only)Time

ArrayString
ObjectString