How to use

toString

method

in

org.apache.calcite.sql.util.SqlString

protected static String toSqlString(SqlNode node) {
  return node.toSqlString(DUMMY).toString();
}

 /**
  * Strips namespace from identifiers of sql
  *
  * @param node
  * @param namespace
  * @param dialect
  * @return
  */
 private String stripNamespace(final SqlNode node,
                final String namespace,
                final SqlDialect dialect) {
  final SqlNode transformedNode = node.accept(
    new SqlShuttle() {
     @Override
     public SqlNode visit(SqlIdentifier id) {
      if (id.names.size() > 1
        && id.names.get(0).toUpperCase().equals(namespace.toUpperCase())) {
       return id.getComponent(1, id.names.size());
      } else {
       return id;
      }
     }
    });
  String result = transformedNode.toSqlString(dialect).toString();
  return result.replace("\n", " ");
 }
}

  new SqlPrettyWriter(CalciteSqlDialect.DEFAULT);
op.unparse(writer, call, 0, 0);
final String s = writer.toSqlString().toString();
if (s.startsWith("OVERLAY(")
  || s.contains(" / 0")

  new SqlPrettyWriter(CalciteSqlDialect.DEFAULT);
op.unparse(writer, call, 0, 0);
final String s = writer.toSqlString().toString();
if (s.startsWith("OVERLAY(")
  || s.contains(" / 0")