87. Activity Report

This advanced SQL exercise is part of the book: Advanced SQL – Practical Techniques and Use-Cases, which includes 100 day-to-day SQL challenges (and solutions), need-to-know advanced features, and key concepts.
 

A semiconductor fabrication plant has 3 operating machines. At the end of each day, each of these machines generates a numeric output that represents the task it completed on that day (step_value). On the following day, the task equals yesterday’s value + 1. For example:

  • On January 1st Machine-A generated the numeric value 1, on the following day the machine generated the value 2, the day after: value 3, and so on (normal operation).
  • On January 1st Machine-B generated the numeric value 1, on the following day the machine generated the value 2, the day after: value 3 ,and so on (normal operation).
  • On January 1st Machine-C generated the numeric value 1, on the following day the machine generated the value 2, the day after: value 5 instead of 3 (an error has occurred).

CREATE TABLE machines_output
(output_date date,
machine varchar(25),
step_value int)
GO

To read more

UpScale Analytics is one of the largest platforms in the world for learning SQL by doing, consisting over 300 SQL exercises at different levels (including solutions), by topics, across over 100 different datasets. More…