How to Count Job Priorities and Generate Chart-Ready Data?

Conditional counting by column

Problem description:

Suppose you have a table with columns jobId, jobName, and Priority, where Priority is an integer between 1 and 5. The goal is to generate a query that counts the number of rows with a specific Priority value and display the results in a format suitable for creating a chart report.

Solution:

To achieve the desired results, you can use a combination of conditional expressions and aggregate functions:

<code class="language-sql">SELECT 
    jobID, JobName,
    SUM(CASE WHEN Priority = 1 THEN 1 ELSE 0 END) AS Priority1,
    SUM(CASE WHEN Priority = 2 THEN 1 ELSE 0 END) AS Priority2,
    SUM(CASE WHEN Priority = 3 THEN 1 ELSE 0 END) AS Priority3,
    SUM(CASE WHEN Priority = 4 THEN 1 ELSE 0 END) AS Priority4,
    SUM(CASE WHEN Priority = 5 THEN 1 ELSE 0 END) AS Priority5
FROM
    Jobs
GROUP BY 
    jobID, JobName;</code>

This query uses a CASE expression to check for a specific Priority value and assign a value of 1 if the condition is true and 0 otherwise. These values ​​are then summed for each jobID and JobName combination.

The

GROUP BY clause ensures that results are grouped by unique values ​​of jobID and JobName, thus providing a breakdown of each job count.

By formatting the results in this way, you can easily embed them into chart reports to visualize the distribution of Priority values ​​for different jobs.

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