SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7be95fd305215236c0a339e38ad9752b9406a71a531e5c645a026220843bd01' 
  AND token = 'xQ4tXKvoWDnZMrZ5RJlTsxnXIvRt4GKL51IIvnM6MPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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