How do I delete a specific row from sqlite with Android Studio (Kotlin)?-CodePudding

I looked through so many tutorials and it's still not working for me. I have a database that looks like this: databaseImage Note that the actual row does not match up with the id. I would like to delete from the actual row rather than using the id.

I have the following function:

`fun deleteDBData(TABLE_NAME:String, rowID : Int) {
    val db = this.writableDatabase
    db.delete(TABLE_NAME, "$ID_COL=$rowID", null)
}`

This however, deletes using the number in the id column rather than the actual row. So with this function, if I tell it to delete rowID = 4, it will delete row 1 rather than row 4. How do I get sqlite to delete row 4?

CodePudding user response：

You are telling to delete the row that has the ID_COL = 4 To delete the 4th row you can run a query like

delete from tran_log where id in (select id from tran_log limit 1 offset 3);

CodePudding user response：

You can find the id of the nth row with LIMIT 1 and OFFSET n - 1 after the ORDER BY clause which I assume should use the column id to sort the rows:

fun deleteDBData(TABLE_NAME: String, n: Long) {
    val db = this.writableDatabase
    db.delete(
        TABLE_NAME,
        "$ID_COL = (SELECT $ID_COL FROM $TABLE_NAME ORDER BY $ID_COL LIMIT 1 OFFSET ? - 1)",
        arrayOf(n.toString())
    )
    db.close()
}