Interface SubQueryConverter


public interface SubQueryConverter
SubQueryConverter provides the interface for classes that convert sub-queries into equivalent expressions.
  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    Returns whether the sub-query can be converted.
    @Nullable RexNode
    convertSubQuery(SqlCall subQuery, SqlToRelConverter parentConverter, boolean isExists, boolean isExplain)
    Converts the sub-query to an equivalent expression.
  • Method Details

    • canConvertSubQuery

      boolean canConvertSubQuery()
      Returns whether the sub-query can be converted.
    • convertSubQuery

      @Nullable RexNode convertSubQuery(SqlCall subQuery, SqlToRelConverter parentConverter, boolean isExists, boolean isExplain)
      Converts the sub-query to an equivalent expression.
      Parameters:
      subQuery - the SqlNode tree corresponding to a sub-query
      parentConverter - sqlToRelConverter of the parent query
      isExists - whether the sub-query is part of an EXISTS expression
      isExplain - whether the sub-query is part of an EXPLAIN PLAN statement
      Returns:
      the equivalent expression or null if the sub-query couldn't be converted