SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f392cd4ea9593a4cd019490469dc093e62fd804be608371984782ea79618027a' 
  AND token = '2kppq3wBhDiYs4NiUMJzW5p8S+B6sufPMyn29XoceYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}