Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd877e91eaa90b71c69ca7310299d76c93d35a3a95e675da760ec8907b83b8f5' 
  AND token = 'lmFrFQM7V1FmKfM+OKQh1wWQxyRfQXtwTlwg4wWFza8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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