SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b715f29775734e07aa2bec905db1ad8337862f5773c674e05a3c4a3be88743a' 
  AND token = 'F6HL2Y+M91h3O4LAVpFLBJ/OuxaKq9tEnd1YxF03PEU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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