SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee038076e95788a768bed12136a832e870adf241b8503cef9479cd1055d2f5c7' 
  AND token = 'moLUkOmnznnwj5yZl/ugaAv61kDYJtc4XU2/cL6hy+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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