ss

def relationSelect(relation: Rep[Relation], field: String, value: Rep[String], resultSchema: Schema): LoweredRelation = {
    val relationArray = getRelationLowered(relation)
    implicit val recTp: TypeRep[Array[String]] = relationArray.tp.typeArguments(0).asInstanceOf[TypeRep[Array[String]]]

    println(s"field: $field, value: $value")
    val relationSchema = getRelationSchema(relation)
    val maps: Map[String, Int] = relationSchema.columns.map(columnName => columnName -> relationSchema.columns.indexOf(columnName)).toMap
    val fieldColumnIndex: Int = maps(field)
    println(s"field: $field, value: $value, maps: $maps")

    dsl"""
      var fieldColumnIndex = $fieldColumnIndex
      var size = 0
      for(i <- 0 until $relationArray(fieldColumnIndex).length) {
        if($relationArray(fieldColumnIndex)(i) == $value) {
          size = size + 1
        }
      }

      var arr = new Array[Array[String]](${relationSchema.size})
      for (k <- 0 until ${relationSchema.size}) {
        arr(k)=new Array[String](size)
      }

      var i = 0
      for(j <- 0 until $relationArray(fieldColumnIndex).length) {
        if(arr(fieldColumnIndex)(j) == $value) {
          for (k <- 0 until ${relationSchema.size}) {
            arr(k)(i)=$relationArray(k)(j)
          }
          i = i + 1
        }
      }
      arr
    """
  }