SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'c1106dc725c7c3e73b5c5a759adf750e0b2da388aa486d6253cbca70a5ba5054' 
  AND token = '/IJzgUOkXLFDFLTsqQidAVH9zPowZW3VGgaOGN/R710=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}