Spark SQL: Generate a row id column with auto increments in CONSECUTIVE integer

Question

I have a databricks notebook written in Scala. And I have this dataframe generated like this:

val df = spark.sql("SELECT ColumnName FROM TableName")

I want to add another column RowID that will automatically populate the rows with integers. I don't want to use the row_number() function. I need CONSECUTIVE integers starting from 1. Is there any other way?

I checked this answer but it does not help me to generate consecutive integers. And monotonically_increasing_id is not working for me. Is this function valid for databricks? Do we need to import some modules?

Thanks!