Kotlin Exposed (KTOR) SELECT last record in Table-CodePudding

How can I select last record in table from database in ktor?

my data class

data class ArticleInfoDTO(
    val id: Int,
    val likes: Int,
    val views: Int,
)

my function

object ArticlesInfo : Table("articles_info") {
    private val id = ArticlesInfo.integer("id")
    private val likes = ArticlesInfo.integer("likes")
    private val views = ArticlesInfo.integer("views")

    fun fetchArticleInfoLastRecord(): ArticleInfoDTO {
        return transaction {
            ArticlesInfo.select {  } // what should I write in curly braces?
        
        }
    }

CodePudding user response：

data class ArticleInfoDTO(
    val id: Int,
    val likes: Int,
    val views: Int,
)

object ArticlesInfo : Table("articles_info") {
    private val id = ArticlesInfo.integer("id")
    private val likes = ArticlesInfo.integer("likes")
    private val views = ArticlesInfo.integer("views")

    fun fetchArticleInfoLastRecord(): ArticleInfoDTO? = transaction {
        ArticlesInfo.selectAll().lastOrNull()?.toArticleInfo()
    }

    private fun ResultRow.toArticleInfo() = ArticleInfoDTO(
        this[id],
        this[likes],
        this[views]
    )
}

CodePudding user response：

I would advise something like:

val lastInfo = ArticlesInfo.selectAll().orderBy(ArticlesInfo.id, SortOrder.DESC).limit(1).singleOrNull()?.toArticleInfo()