User-defined functions (UDFs) are a feature of SQL supported by BigQuery that enables a user to create a function using another SQL expression or JavaScript. These functions accept columns of input and perform actions, returning the result of those actions as a value.
The community folder contains community-contributed functions that perform some actions in BigQuery. The migration folder contains sub-folders such as teradata, redshift, and oracle which contain community-contributed functions that replicate the behavior of proprietary functions in other data warehouses. These functions can help you achieve feature parity in a migration from another data warehouse to BigQuery.
All UDFs within this repository will be automatically created under the bqutil
project under publicly shared datasets. Queries can then reference the shared
UDFs via bqutil.<dataset>.<function>().
If you want to create and use the UDFs from this repository in your own BigQuery
dataset, you must provide your own dataset name in the following bqutil
command:
bq query --project_id YOUR_PROJECT_ID --dataset_id YOUR_DATASET_ID --nouse_legacy_sql < SQL_FILE_NAME
Once the UDF is created in your BigQuery project, you can invoke it using the
fully-qualified UDF name (e.g. <PROJECT>.<DATASET>.<UDF_NAME>()).
If you are pasting and executing the UDF DDL statement in the BigQuery Console, you must modify the UDF name to include your desired dataset, and optionally, the project ID:
CREATE OR REPLACE FUNCTION your_dataset.function_name() . . .
or
CREATE OR REPLACE FUNCTION project_id.your_dataset.function_name() . . .
If you are interested in contributing UDFs to this repository, please see the instructions to get started.