MySQL 8.0

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CREATE TABLE test(data JSON)
INSERT INTO test (data) VALUES ('{"type":"user" , 
"content" : { "username": "jdoe", "firstname" : "John", "lastname" : "Doe" } }');

INSERT INTO test (data) VALUES ('{"type": "user \\\"Test\\\"" , 
"content" : { "username": "jdoe", "firstname" : "John", "lastname" : "Doe" } }');
SELECT json_extract(data,'$.type') FROM test;

json_extract(data,'$.type')

"user"

"user "Test""

SELECT json_value(data,'$.type')
FROM test;

json_value(data,'$.type')

user

user "Test"