SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2747dcadcf32d97b8cace1cd6757119f3cf7e4f73952df76a3fec1bd25247d3e' 
  AND token = 'AQyC2JP23AGWUDno2WeNopIteXhs26KTpFK5NDMDQ/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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