Table functions (built in)
GoogleSQL for BigQuery supports built-in table functions.
This topic includes functions that produce columns of a table.
You can only use these functions in the FROM clause.
Function list
| Name | Summary |
|---|---|
APPENDS
|
Returns all rows appended to a table for a given time range.
For more information, see Time series functions. |
CHANGES
|
Returns all rows that have changed in a table for a given time range.
For more information, see Time series functions. |
EXTERNAL_OBJECT_TRANSFORM
|
Produces an object table with the original columns plus one or more additional columns. |
GAP_FILL
|
Finds and fills gaps in a time series.
For more information, see Time series functions. |
RANGE_SESSIONIZE
|
Produces a table of sessionized ranges.
For more information, see Range functions. |
EXTERNAL_OBJECT_TRANSFORM
EXTERNAL_OBJECT_TRANSFORM(TABLEobject_table_name,transform_types_array)
Description
This function returns a transformed object table with the original columns plus
one or more additional columns, depending on the transform_types values
specified.
This function only supports object tables as inputs. Subqueries or any other types of tables aren't supported.
object_table_name is the name of the object table to be transformed, in
the format dataset_name.object_table_name.
transform_types_array is an array of STRING literals. Currently, the only
supported transform_types_array value is SIGNED_URL. Specifying SIGNED_URL
creates read-only signed URLs for the objects in the identified object table,
which are returned in a signed_url column. Generated signed URLs are
valid for 6 hours.
Return Type
TABLE
Example
Run the following query to return URIs and signed URLs for the objects in the
mydataset.myobjecttable object table.
SELECTuri,signed_url
FROMEXTERNAL_OBJECT_TRANSFORM(TABLEmydataset.myobjecttable,['SIGNED_URL']);
--Theprecedingstatementreturnsresultssimilartothefollowing:
/*-----------------------------------------------------------------------------------------------------------------------------*
| uri | signed_url |
+-----------------------------------------------------------------------------------------------------------------------------+
| gs://myobjecttable/1234_Main_St.jpeg | https://storage.googleapis.com/mybucket/1234_Main_St.jpeg?X-Goog-Algorithm=1234abcd... |
+-----------------------------------------------------------------------------------------------------------------------------+
| gs://myobjecttable/345_River_Rd.jpeg | https://storage.googleapis.com/mybucket/345_River_Rd.jpeg?X-Goog-Algorithm=2345bcde... |
*-----------------------------------------------------------------------------------------------------------------------------*/