SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3eeb3686ec03ca825410865260bbdc9b355e3bf71b1d94179a9f078ff3cca49' 
  AND token = 'U9zgYh64ENPH9px4IFSaNvUOhGsySLOrW9TwiKjDHIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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