SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cdf0ae55b8db623e68bda9861ff39073627e783d6f6531851aae5550d5c642ba' 
  AND token = 'glQ0B4DnvV5D3JS4UvGEcQuFX0nCEr0cacgqS8mXcLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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