private void parseCorrelTable(RelNode relNode, Result x) {
    for (CorrelationId id : relNode.getVariablesSet()) {
      correlTableMap.put(id, x.qualifiedContext());
    }
  }
Removes cast from string.

<p>For example, {@code x > CAST('2015-01-07' AS DATE)}
becomes {@code x > '2015-01-07'}.
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/jdbc/HiveJdbcImplementor.java