This SQL statement is combining the results of two select queries using the UNION operator.

Here's a step-by-step breakdown:

1. `SELECT employee_id FROM employees`: This part of the statement selects the `employee_id` from the `employees` table. It will return a list of all current employee IDs.

2. `SELECT employee_id FROM former_employees`: This part of the statement selects the `employee_id` from the `former_employees` table. It will return a list of all former employee IDs.

3. `UNION`: This is a set operator that combines the result sets of two or more SELECT statements. It removes duplicate rows from the result sets.

So, the entire statement `SELECT employee_id FROM employees UNION SELECT employee_id FROM former_employees;` will return a list of employee IDs from both the `employees` and `former_employees` tables, removing any duplicates. This means if an employee ID is present in both tables, it will appear only once in the final result set.

Question

This SQL statement is combining the results of two select queries using the UNION operator.

Here's a step-by-step breakdown:

1. `SELECT employee_id FROM employees`: This part of the statement selects the `employee_id` from the `employees` table. It will return a list of all current employee IDs.

2. `SELECT employee_id FROM former_employees`: This part of the statement selects the `employee_id` from the `former_employees` table. It will return a list of all former employee IDs.

3. `UNION`: This is a set operator that combines the result sets of two or more SELECT statements. It removes duplicate rows from the result sets.

So, the entire statement `SELECT employee_id FROM employees UNION SELECT employee_id FROM former_employees;` will return a list of employee IDs from both the `employees` and `former_employees` tables, removing any duplicates. This means if an employee ID is present in both tables, it will appear only once in the final result set.

Knowee AI · Accepted Answer

This SQL statement is combining the results of two select queries using the UNION operator.

Here's a step-by-step breakdown:

1. `SELECT employee_id FROM employees`: This part of the statement selects the `employee_id` from the `employees` table. It will return a list of all current employee IDs.

2. `SELECT employee_id FROM former_employees`: This part of the statement selects the `employee_id` from the `former_employees` table. It will return a list of all former employee IDs.

3. `UNION`: This is a set operator that combines the result sets of two or more SELECT statements. It removes duplicate rows from the result sets.

So, the entire statement `SELECT employee_id FROM employees UNION SELECT employee_id FROM former_employees;` will return a list of employee IDs from both the `employees` and `former_employees` tables, removing any duplicates. This means if an employee ID is present in both tables, it will appear only once in the final result set.

Consider the following SQL statement:SELECT employee_id FROM employeesUNIONSELECT employee_id FROM former_employees;What does this statement do

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Consider the following SQL statement:

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