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create table test_table(id_col number, blob_col blob);
insert into test_table(id_col) values(1);
1 rows affected
insert into test_table(id_col) values(1);
1 rows affected
DECLARE
v_json_result_clob CLOB;
BEGIN
SELECT listagg(JSON_ARRAY(
JSON_OBJECT(
KEY 'id_col' VALUE ID_col,
KEY 'blob_col' VALUE blob_col RETURNING CLOB
)
RETURNING CLOB
)) INTO v_json_result_clob FROM TEST_TABLE WHERE ID_col = 1; -- apex_application.g_x01;
dbms_output.put_line(v_json_result_clob);
END;
/
1 rows affected
dbms_output:
[{"id_col":1,"blob_col":null}][{"id_col":1,"blob_col":null}]