SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cf23b08c7a7791a7eb5aeddec98493ab376576d29f2b1ba5230decc11082e16' 
  AND token = 'zAO3Ti+eAYvlDxtOKJWI43ZqlGbX6PHN4YwIPxZ69vo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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