SELECT
  * 
INTO OUTFILE '/full_path/to/load_data.csv' 
  FIELDS TERMINATED BY ',' 
  OPTIONALLY ENCLOSED BY '"' 
  LINES TERMINATED BY "\n" 
  ESCAPED BY '\'
FROM
  tbl_example
WHERE
  id IN ( 
    SELECT
      id 
    FROM
      tbl_reration
    WHERE
      status = 'true' 
  );