Allow per-field length declaration for varchar and char types in BI Connector
Usually in defining schemas for SQL databases, you can specify a max length for the size of a char or varchar column. It'd be nice to have the ability to do that in a schema that's passed to the mongosqld BI Connector process.
The only option now is to specify a max varchar size that applies to all varchar fields. It'd be nice to be able to define this on a per field basis.
This is an issue for a customer I'm working with because of the way their BI tool allocates memory for temporary objects created when bridging the SQL data source and their front-end app -- shorter varchars can significantly improve memory utilization and latency.
Peter Kim
shared this idea
MongoDB has chosen to not enhance the BI Connector any further. The SQL Interface will replace the BI Connector. This issue for BI Connector regarding the field length is imposed by the underlying MySQL dialect. The SQL Interface does other utilize MySQL for SQL to MQL translation, instead it uses MongoSQL (a sql-92 compatible dialect).