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TJ Banghart commented on CALCITE-5346: -------------------------------------- I was looking at this again and it seems that user-defined types can be used to achieve generic type aliases. The issue is that they are locked to specific schemas and must be scoped within expressions: {{SELECT CAST(foo as <schema>.myType) FROM <schema>.<table>;}} It would be great to be able to define types for all schema that one could declare at root: { version: '1.0', defaultSchema: 'mongo', schemas: [ Schema... ], *types: [Types... ]* } Schema specific types would take precedent but then we could check global custom types and default to the standard. Does this seem like a feasible option? I think we wouldn't have to touch the parser much if at all. > Support for type aliases > ------------------------ > > Key: CALCITE-5346 > URL: https://issues.apache.org/jira/browse/CALCITE-5346 > Project: Calcite > Issue Type: New Feature > Reporter: Will Noble > Assignee: Will Noble > Priority: Major > > We would like to support some sort of type alias functionality in order to > map certain [BigQuery > types|https://cloud.google.com/bigquery/docs/reference/standard-sql/data-types] > to ISO types, e.g. {{STRING}} -> {{VARCHAR}}. -- This message was sent by Atlassian Jira (v8.20.10#820010)