in connectors/spark-iotdb-table-connector/spark-iotdb-table-common/src/main/scala/org/apache/iotdb/spark/table/db/read/IoTDBExpressionSQLBuilder.scala [77:99]
private def visitGeneralScalarExpression(expr: GeneralScalarExpression): String = {
// <=> is unsupported
expr.name() match {
case "IS_NULL" => visitIsNull(expr)
case "IS_NOT_NULL" => visitIsNotNull(expr)
case "STARTS_WITH" => visitStartsWith(expr)
case "ENDS_WITH" => visitEndsWith(expr)
case "CONTAINS" => visitContains(expr)
case "IN" => visitIn(expr)
case "=" => visitEqualTo(expr)
case "<>" => visitNotEqualTo(expr)
case "<" => visitLess(expr)
case "<=" => visitLessOrEqual(expr)
case ">" => visitGreater(expr)
case ">=" => visitGreaterOrEqual(expr)
case "AND" => visitAnd(expr.asInstanceOf[And])
case "OR" => visitOr(expr.asInstanceOf[Or])
case "NOT" => visitNot(expr.asInstanceOf[Not])
case "ALWAYS_TRUE" => visitAlwaysTrue()
case "ALWAYS_FALSE" => visitAlwaysFalse()
case _ => throw new UnsupportedOperationException("Unsupported push down expression: " + expr)
}
}