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POSQL query one to many relationship
 

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    <p>I have a table for Employees and another table with Training. The training table contains various training classes that the employees have completed. We have mandatory security awareness training, so every employee must complete this training class. I’m having trouble running a query that will return ALL employees' either listed completing the training or not.</p> <p>Example Employee table</p> <pre><code>╔════╦══════╗ ║ ID ║ NAME ║ ╠════╬══════╣ ║ 1 ║ Bob ║ ║ 2 ║ Tom ║ ║ 3 ║ John ║ ╚════╩══════╩ </code></pre> <p>Example Training table</p> <pre><code>╔════╦══════════════╦════════════════════╗ ║ ID ║ DEPARTMENT_ID║ CLASS ║ ╠════╬══════════════╬════════════════════╣ ║ 1 ║ 1 ║ Security Awareness ║ ║ 2 ║ 1 ║ Workplace Safety ║ ║ 3 ║ 2 ║ Security Awareness ║ ╚════╩══════════════╩════════════════════╝ </code></pre> <p>Target result</p> <pre><code>╔════╦══════╦════════════════════╗ ║ ID ║ NAME ║ CLASS ║ ╠════╬══════╬════════════════════╣ ║ 1 ║ Bob ║ Security Awareness ║ ║ 2 ║ Tom ║ Security Awareness ║ ║ 3 ║ John ║ (null) ║ ╚════╩══════╩════════════════════╝ </code></pre> <p>The query that I am using is </p> <pre><code>SELECT employee.id, employee.name, training.class FROM employee JOIN training ON employee.id = training.department_id WHERE training.class LIKE '%SECURITY%' ORDER BY employee_id </code></pre> <p>The employee missing the "Security Awareness" class just don't appear, and falls through the cracks.</p>
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A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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