[CALCITE-4179] org.apache.calcite.jdbc package polluting core Calcite planning packages

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: core
• Assignee: Unassigned
• Reporter: Laurent Goujon
• Created: 17/Aug/20 23:05
• Updated: 20/Aug/20 15:09

Description

Several classes under org.apache.calcite.jdbc package are used by planning classes. As those JDBC classes are some form of implementation, it means the Calcite API has some kind of coupling, causing extra challenges for alternate implementations.

One of the central classes of org.apache.calcite.jdbc is CalciteSchema which represents the catalog space. This class is designed to load the entire catalog and hold it in memory, which is a problem for those having catalogs too large for this to be practical. This class is sometimes used instead of the more generic Schema and SchemaPlus classes.

Another similar class is CalcitePrepare: the class is for example used by org.apache.calcite.prepare.Prepare instead of the dependency being the other way around.

Issue Links

• relates to: CALCITE-1525 Use "Planner" to handle query preparation process in CalcitePrepareImpl