Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cfe755954bf173f564072d911a0b4e17cba5c7d9ab0633ade8a63a810a4d373' 
  AND token = 'MnVrj5g13eUkGfKem9ez90FTgUqmcBr3oNTYWrW6+1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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