SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ee0771f064d4762effac8f7b3b9bb0e2cca8b9ae2027c0485a8229bbd1bb8872' 
  AND token = 'fBI1l2Ztqk6nJc8K7F7xP+13Bvt+sElAO9fMt/CrgVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}