SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fc32279b390bb8452cf71d324b989fa6425ae3594df9b33c06de67676d65a42' 
  AND token = '+T3H9YEBpzZwbRVZuWZCpICIQs/axB2poCSA5Oceg3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}