[CALCITE-5395] RelToSql converter fails when SELECT * is under a semi-join node

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.32.0
• Fix Version/s: 1.33.0
• Labels: pull-request-available
• Assignee: Jiajun Xie
• Reporter: Leonid Chistov
• Created: 21/Nov/22 10:22
• Updated: 07/Feb/23 22:33
• Resolved: 12/Dec/22 09:45

Description

The following test case would fail if added to RelToSqlConverterTest.java:

@Test void testUnionUnderSemiJoinNode() {
  final RelBuilder builder = relBuilder();
  final RelNode base = builder
      .scan("EMP")
      .scan("EMP")
      .union(true)
      .build();
  final RelNode root = builder
      .push(base)
      .scan("DEPT")
      .join(
          JoinRelType.SEMI, builder.equals(
              builder.field(2, 1, "DEPTNO"),
              builder.field(2, 0, "DEPTNO")))
      .project(builder.field("DEPTNO"))
      .build();
  toSql(root);
} 

The exception is:

Index 7 out of bounds for length 1
java.lang.IndexOutOfBoundsException: Index 7 out of bounds for length 1
    at java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:64)
    at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:70)
    at java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:266)
    at java.base/java.util.Objects.checkIndex(Objects.java:359)
    at java.base/java.util.ArrayList.get(ArrayList.java:427)
    at org.apache.calcite.sql.SqlNodeList.get(SqlNodeList.java:160)
    at org.apache.calcite.rel.rel2sql.RelToSqlConverter$AliasReplacementShuttle.visit(RelToSqlConverter.java:197)
    at org.apache.calcite.rel.rel2sql.RelToSqlConverter$AliasReplacementShuttle.visit(RelToSqlConverter.java:179)
    at org.apache.calcite.sql.SqlIdentifier.accept(SqlIdentifier.java:324)
    at org.apache.calcite.sql.util.SqlShuttle$CallCopyingArgHandler.visitChild(SqlShuttle.java:134)
    at org.apache.calcite.sql.util.SqlShuttle$CallCopyingArgHandler.visitChild(SqlShuttle.java:101)
    at org.apache.calcite.sql.SqlOperator.acceptCall(SqlOperator.java:954)
    at org.apache.calcite.sql.util.SqlShuttle.visit(SqlShuttle.java:68)
    at org.apache.calcite.sql.util.SqlShuttle.visit(SqlShuttle.java:41)
    at org.apache.calcite.sql.SqlCall.accept(SqlCall.java:161)
    at org.apache.calcite.rel.rel2sql.RelToSqlConverter.visitAntiOrSemiJoin(RelToSqlConverter.java:261) 

What happens is that `AliasReplacementShuttle` expects a select list as a source of replacement, but cannot handle a case when select node has a `select *` form.

In case of current test, `union` is transformed to `select *` form before semi-join handling occurs.

Issue Links

• links to: GitHub Pull Request #2983