Android Sqlite: Check if row exists in table

Question

I have an array of strings that need to be checked if exists in a table before inserting them in order to avoid duplicates. What is the SQL query and how do I substitute the

Answer 1

Use SELECT EXIST to limit only the result to 1 or 0 and LIMIT 1 make the query execute faster:

fun exists(): Boolean {
    var sql = "SELECT EXISTS (SELECT * FROM $tableName WHERE $someColumn 
        = $someValue LIMIT 1)"
    val cursor = db?.rawQuery(sql, null)
    cursor?.moveToFirst()
    return if (cursor?.getInt(0) == 1) {
        cursor?.close()
       true
    } else {
      cursor?.close()
      false
    }

}