[GitHub] [calcite] jinxing64 opened a new pull request #1351: [CALCITE-3226] Expand view should keep the alias expanded view

[GitBox <gi...@apache.org>]

jinxing64 opened a new pull request #1351: [CALCITE-3226] Expand view should keep the alias expanded view 
URL: https://github.com/apache/calcite/pull/1351
 
 
   In current implementation of `RelBuilder::scan ` (https://github.com/apache/calcite/blob/master/core/src/main/java/org/apache/calcite/tools/RelBuilder.java#L1048), the alias can be derived and recorded into `Frame` only when the `RelNode` is a `TableScan` (https://github.com/apache/calcite/blob/master/core/src/main/java/org/apache/calcite/tools/RelBuilder.java#L2754).
   But when `RelBuilder::scan` from an expanded view, the node is not a `TableScan` and the alias is not kept.  Below test failed - we cannot reference a field by alias "MYVIEW".
   ```
     @Test public void testExpandViewShouldKeepAlias() throws SQLException {
       try (Connection connection = DriverManager.getConnection("jdbc:calcite:")) {
         final Frameworks.ConfigBuilder configBuilder =
             expandingConfig(connection);
         final RelOptTable.ViewExpander viewExpander =
             (RelOptTable.ViewExpander) Frameworks.getPlanner(configBuilder.build());
         final RelFactories.TableScanFactory tableScanFactory =
             RelFactories.expandingScanFactory(viewExpander,
                 RelFactories.DEFAULT_TABLE_SCAN_FACTORY);
         configBuilder.context(Contexts.of(tableScanFactory));
         final RelBuilder builder = RelBuilder.create(configBuilder.build());
         RelNode node =
             builder.scan("MYVIEW")
                 .project(
                     builder.field(1, "MYVIEW", "EMPNO"),
                     builder.field(1, "MYVIEW", "ENAME"))
                 .build();
         String expected =
             "LogicalProject(EMPNO=[$0], ENAME=[$1])\n"
                 + "  LogicalFilter(condition=[=(1, 1)])\n"
                     + "    LogicalTableScan(table=[[scott, EMP]])\n";
         assertThat(node, hasTree(expected));
       }
     }
   ```

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services