[CALCITE-3381] When generating SQL for BigQuery (via unparsing), convert Calcite SQL types to BigQuery types

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.21.0
• Fix Version/s: 1.22.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Rui Wang
• Reporter: Kirill Kozlov
• Created: 30/Sep/19 17:31
• Updated: 06/Mar/20 04:35
• Resolved: 07/Dec/19 04:51

Description

When using `SqlImplementor.SimpleContext#toSql` with BigQuerySqlDialect on Rel nodes containing `CAST` need to convert Calcite SqlTypeName to BigQuery supported types (https://cloud.google.com/bigquery/docs/reference/standard-sql/data-types).

I believe this can be accomplished by Overriding BigQuerySqlDialect#getCastSpec method.

Example: VARCHAR should become a STRING, BOOLEAN - BOOL, and so on.

Issue Links

• is related to: CALCITE-3568 BigQuery, Hive, Spark SQL dialect don't support nested aggregates
• links to: GitHub Pull Request #1482
• links to: GitHub Pull Request #1561
• links to: GitHub Pull Request #1588