SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccd964334db9b04f82081dd282723283c5d4e671ec24c841377c0671ec798b15' 
  AND token = 'Ok+QwpeAAavZu8j9p+vu9fCxRuJBsD9TqMtea8/bfRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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