Error report -
No more data to read from socket

ALTER TABLE EMP ADD JSON_DATA VARCHAR2(100);
update EMP SET JSON_DATA ='{"data": {"ename": "MILLER"}}'WHERE ENAME ='MILLER' ;
update EMP SET JSON_DATA ='{"data": {"ename": "KING"}}'WHERE ENAME ='KING' ;
commit;

DECLARE
    l_ename    VARCHAR2(20) := 'MILLER';
    l_exists   NUMBER;
BEGIN
    SELECT
        1
    INTO l_exists
    FROM
        emp,
        JSON_TABLE ( json_data, '$.data'
                COLUMNS (
                    newename VARCHAR2 PATH '$.ename'
                )
            )
        t
    WHERE
        deptno = 10
        AND t.newename = 'MILLER';--l_ename 

END;