SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '714348d4f9527139d94e57edb3606e4eadd434e5ef31ba9ead054d59b46781bc' 
  AND token = 'I+DC4dUNZphhlsCXdtJGdmiTr4pVMHEA6+ydqHOzuWA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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