SQLite 3.27

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CREATE TABLE "tbl_employee" (
    "ID"    INTEGER,
    "FirstName"    TEXT NOT NULL,
    "LastName"    TEXT NOT NULL,    
    PRIMARY KEY("ID")
);
CREATE TABLE "tbl_task" (
    "ID"    INTEGER,
    "Description"    TEXT NOT NULL,
    PRIMARY KEY("ID")
);
CREATE TABLE "tbl_emp_task" (
    "emp_id"    INTEGER,
    "task_id"    INTEGER,
    FOREIGN KEY("task_id") REFERENCES "tbl_task"("ID") ON UPDATE CASCADE ON DELETE CASCADE,
    FOREIGN KEY("emp_id") REFERENCES "tbl_employee"("ID") ON UPDATE CASCADE ON DELETE CASCADE,
    PRIMARY KEY("emp_id","task_id")
);
INSERT INTO tbl_employee ("ID", "FirstName", "LastName") VALUES (1, 'Tom', 'Brown'), (2, 'Robert', 'Miller'), (3, 'John', 'Smith');
INSERT INTO tbl_task ("ID", "Description") VALUES (1, 'answering phones'), (2, 'preparing meeting'), (3, 'receiving visitors'), (4, 'Maintaining security'), (5, 'Arranging couriers');
INSERT INTO tbl_emp_task ("emp_id", "task_id") VALUES (1,1), (1,2), (1,4), (2,2),(2,3),(2,5);
With CTE(EID,TDESC) AS
    (SELECT
        ET.emp_ID,
        T.Description
    FROM tbl_emp_task AS ET
    INNER JOIN tbl_task AS T
    ON T.ID=ET.task_id
    ORDER BY Lower(T.Description))
SELECT
    E.FirstName || ' ' || E.LastName As FullName,
    COALESCE(C.AssignedTasks, 'No assigned Tasks') AS AssignedTasks
FROM tbl_employee AS E
LEFT JOIN
    (SELECT
        EID,
        GROUP_CONCAT(TDESC, ', ') AS AssignedTasks
    FROM CTE GROUP BY EID) AS C
ON C.EID=E.ID
GROUP BY E.FirstName || ' ' || E.LastName ORDER BY E.LastName, E.FirstName


FullName
AssignedTasks


Tom Brown
answering phones, Maintaining security, preparing meeting

Robert Miller
Arranging couriers, preparing meeting, receiving visitors

John Smith
No assigned Tasks

FullName	AssignedTasks
Tom Brown	answering phones, Maintaining security, preparing meeting
Robert Miller	Arranging couriers, preparing meeting, receiving visitors
John Smith	No assigned Tasks