MySQL 8.0

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create table department(documentid int, jsondocument json);

INSERT INTO department VALUES
(1,'{"department":{
"deptid":"d1",
"deptname":"Marketing",
"deptroom":"Room 7",
"deptphone":["465-8541","465-8542","465-8543"],
"employee":[{
"empid":"e1",
"empname":"Mary Jones",
"empphone":"465-8544",
"empemail":["mjones@gmail.com","mjones@company.com"]},
{
"empid":"e2",
"empname":"Tom Robinson",
"empphone":"465-8545",
"empemail":["trobinson@gmail.com","trobinson@company.com"]},
{
"empid":"e3",
"empname":"Olivia Johnson",
"empphone":"465-8546",
"empemail":["ojohnson@gmail.com","ojohnson@company.com"]}
]}} ' );

INSERT INTO department VALUES
(2,'{"department":{
"deptid":"d2",
"deptname":"Research",
"deptroom":"Room 5",
"deptphone":["465-8551","465-8552","465-8553"],
"employee":[{
"empid":"e4",
"empname":"Bob Robins",
"empphone":"465-8554",
"empemail":["brobins@gmail.com","brobins@company.com"]},
{
"empid":"e5",
"empname":"Albert Mathers",
"empphone":"465-8555",
"empemail":["amathers@gmail.com","amathers@company.com"]},
{
"empid":"e6",
"empname":"Amy Quincy",
"empphone":"465-8556",
"empemail":["aquincy@gmail.com","aquincy@company.com"]}
]}} ' );
INSERT INTO department VALUES
(3,'{"department":{
"deptid":"d3",
"deptname":"Sales",
"deptroom":"Room 14",
"deptphone":["465-8641","465-8562","465-8563"],
"employee":[{
"empid":"e7",
"empname":"Robin Thompson",
"empphone":"465-8564",
"empemail":["rthompson@gmail.com","rthompson@company.com"]},
{
"empid":"e8",
"empname":"Michelle Courts",
"empphone":"465-8565",
"empemail":["mcourts@gmail.com","mcourts@company.com"]},
{
"empid":"e9",
"empname":"Jon Davidson",
"empphone":"465-8566",
"empemail":["jdavidson@gmail.com","jdavidson@company.com"]}
]}} ' );
select
    jsondocument->'$.department.deptname' as deptname, 
    jsondocument->'$.department.employee[*].empname' as employees
from department
HAVING deptname = 'Marketing';


deptname
employees


"Marketing"
["Mary Jones", "Tom Robinson", "Olivia Johnson"]