SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0de6814cfa41ccc4618be2de6bae106a49018725b48012ea4dead0859a128979' 
  AND token = 'sWunvU7N1FKLsqmCwneXO4f2DgxoMNkLDe3RQ2QFF+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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