[KYLIN-819] Fix necessary ColumnMetaData order for Calcite (Optic)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: v0.7.1
• Fix Version/s: v0.7.2
• Component/s: Driver - JDBC
• Flags: Important
• Assignee: liyang
• Reporter: Sébastien Jelsch
• Created: 08/Jun/15 10:01
• Updated: 21/Jul/15 07:46
• Resolved: 21/Jul/15 07:38

Description

The following code

Class.forName("org.apache.kylin.jdbc.Driver");
    
Connection con = DriverManager.getConnection("jdbc:kylin://localhost:7070/simple_project", "admin", "KYLIN");

DatabaseMetaData dmd = con.getMetaData();
ResultSet result = dmd.getColumns(null, null, "SIMPLE_FACT", "%");

while(result.next()) {
  System.out.println("dataType: "+ result.getInt(5));
}

results in the following error message:

Exception in thread "main" java.lang.RuntimeException: cannot convert to long (net.hydromatic.optiq.runtime.AbstractCursor$StringAccessor@16107cce)
  at net.hydromatic.optiq.runtime.AbstractCursor$AccessorImpl.cannotConvert(AbstractCursor.java:287)
  at net.hydromatic.optiq.runtime.AbstractCursor$AccessorImpl.getLong(AbstractCursor.java:243)
  at net.hydromatic.optiq.runtime.AbstractCursor$AccessorImpl.getInt(AbstractCursor.java:239)
  at net.hydromatic.avatica.AvaticaResultSet.getInt(AvaticaResultSet.java:220)
  at org.mustangore.kylin.KylinConnection.newConnection(KylinConnection.java:32)
  at org.mustangore.kylin.KylinConnection.main(KylinConnection.java:20)

Tried with apache-calcite-0.9.1 and apache-calcite-0.9.2 .

Reason and fix
SQLTypeMap uses HasMap, but Calcite (Optic) needs specific order. So using LinkedHashMap fixes this issue.