SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31d2b1b2096b5259f609985bcc5917246906b3a42b73507b5aceda0c7de47b2d' 
  AND token = 'unBcsvIrzIoouIEjs0ojwpnizgrcWzgG/GUMBsu+Azo=' 
  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"
    }
  }
}