예외처리(undefined, null, length)

try {
  const sql = `
                SELECT
                  total_count ,
                  current_count
                FROM
                  content_test
                WHERE
                  idx = ${test_no}
              `;

  const result = await db.query(sql).catch(() => {return false});

  if (result.length === 0) return false;
  return result[0].total_count === result[0].current_count;
} catch {
  return false;
}

----------------------------------------
let t = undefined or null
t.length === 0


    try {
  const sql = `
                SELECT
                  total_count ,
                  current_count
                FROM
                  content_test
                WHERE
                  idx = ${test_no}
              `;

  const result = await db.query(sql).catch(() => {return null});

  if (result?.length > 0) {
    return false;
  }else{
    return result[0].total_count === result[0].current_count;
  } 
} catch {
  return false;
}