def test_get_fields(app_context: AppContext) -> None:
"""
Test the custom ``_get_fields`` method.
The method adds custom labels (aliases) to the columns to prevent
collision when referencing record fields. Eg, if we had these two
columns:
name STRING
project STRUCT<name STRING>
One could write this query:
SELECT
`name`,
`project`.`name`
FROM
the_table
But then both columns would get aliased as "name".
The custom method will replace the fields so that the final query
looks like this:
SELECT
`name` AS `name`,
`project`.`name` AS project__name
FROM
the_table
"""
from superset.db_engine_specs.bigquery import BigQueryEngineSpec
columns = [{"name": "limit"}, {"name": "name"}, {"name": "project.name"}]
fields = BigQueryEngineSpec._get_fields(columns)
# generic SQL
query = select(fields)
assert (
str(query)
== 'SELECT "limit" AS "limit", name AS name, "project.name" AS project__name'
)
# BigQuery-specific SQL
try:
from pybigquery.sqlalchemy_bigquery import BigQueryDialect
except ModuleNotFoundError:
return
assert str(query.compile(dialect=BigQueryDialect())) == (
"SELECT `limit` AS `limit`, `name` AS `name`, "
"`project`.`name` AS `project__name`"
)
def test_get_fields() -> None:
"""
Test the custom ``_get_fields`` method.
The method adds custom labels (aliases) to the columns to prevent
collision when referencing record fields. Eg, if we had these two
columns:
name STRING
project STRUCT<name STRING>
One could write this query:
SELECT
`name`,
`project`.`name`
FROM
the_table
But then both columns would get aliased as "name".
The custom method will replace the fields so that the final query
looks like this:
SELECT
`name` AS `name`,
`project`.`name` AS project__name
FROM
the_table
"""
from superset.db_engine_specs.bigquery import BigQueryEngineSpec
columns = [{"name": "limit"}, {"name": "name"}, {"name": "project.name"}]
fields = BigQueryEngineSpec._get_fields(columns)
query = select(fields)
assert str(query.compile(dialect=BigQueryDialect())) == (
"SELECT `limit` AS `limit`, `name` AS `name`, "
"`project`.`name` AS `project__name`"
)
