Calculating Total Power Consumed for a Given Metal in the Last One Hour of a Process

In this article, we will explore how to calculate the total power consumed by a metal in the last one hour of a process. This involves joining two tables, Metal_Master_Data and Metal_Interval_Data, based on the metal ID and then filtering the data to include only the readings within the last one hour.

Background

The Metal_Master_Data table contains information about the actual start and end timestamps for each metal, while the Metal_Interval_Data table has electricity consumption readings at specific timestamps. We want to calculate the total power consumed by a metal in the last one hour of the process, which means we need to join these two tables based on the metal ID and then perform a date-based filter.

Table Structure

The Metal_Master_Data table has the following columns:

• MetalID: The unique identifier for each metal.
• MetalStartActual: The actual start timestamp for the metal process.
• MetalStartPlanned: The planned start timestamp for the metal process (not used in this calculation).
• MetalEndActual: The actual end timestamp for the metal process.
• MetalEndPlanned: The planned end timestamp for the metal process (not used in this calculation).

The Metal_Interval_Data table has the following columns:

• MetalID: The unique identifier for each metal.
• TreatID: The treatment ID for the metal.
• Plant: The plant ID where the metal is processed.
• ElctrctyConsumed: The electricity consumption reading at the specified timestamp.
• ReadingTime: The timestamp when the electricity consumption reading was taken.

SQL Query

The provided SQL query joins the two tables based on the metal ID and calculates the total power consumed by summing up the electricity consumption readings within the last one hour:

SELECT A.MetalID, SUM(B.ElctrctyConsumed) TotalConsumed
FROM Metal_Master_Data A
INNER JOIN Metal_Interval_Data B ON A.MetalID = B.MetalID
WHERE B.ReadingTime BETWEEN DATEADD(HH,-1,A.MetalEndActual) AND A.MetalEndActual
GROUP BY A.MetalID;

Explanation

Here’s a step-by-step explanation of the SQL query:

• SELECT A.MetalID, SUM(B.ElctrctyConsumed) TotalConsumed: We select the metal ID and calculate the total power consumed by summing up the electricity consumption readings.
• FROM Metal_Master_Data A INNER JOIN Metal_Interval_Data B ON A.MetalID = B.MetalID: We join the two tables based on the metal ID using an inner join. This ensures that we only include rows where there is a match in both tables.
• WHERE B.ReadingTime BETWEEN DATEADD(HH,-1,A.MetalEndActual) AND A.MetalEndActual: We filter the data to include only readings within the last one hour by checking if the reading time is between one hour before and the actual end timestamp of the metal process.

Example Use Case

Suppose we have the following data in both tables:

Metal_Master_Data:

Metal_Interval_Data:

The SQL query would return:

This shows that the total power consumed by metal with ID 123456 in the last one hour is 43150, and the total power consumed by metal with ID 123478 in the last one hour is 150.

Last modified on 2024-10-25