Suppose you have a very large dataset - far too large to hold in memory - with duplicate entries. You want to know how many duplicate entries, but your data isn't sorted, and it's big enough that sorting and counting is impractical. How do you estimate how many unique entries the dataset contains? It's easy to see how this could be useful in many applications, such as query planning in a database:
火狐体育有限公司(火狐体育直播平台)成立于2013年11月6日,火狐体育登录地址可通过官网下载查看,目前经营范围有游戏开发,软文制作,创意策划、体育直播等,可以为大家打来各种体验。。
Just stop, y’all. It’s a waste of your time and your effort. Put down your Google search for an email regular expression, take a step back, and breathe. There’s a famous quote that goes: Some people, when confronted with a problem, think, “I know, I’ll use regular expressions.” Now they have two problems. — Jamie Zawinski Here’s a fairly common code sample from Rails Applications with some sort of
リリース、障害情報などのサービスのお知らせ
最新の人気エントリーの配信
処理を実行中です
j次のブックマーク
k前のブックマーク
lあとで読む
eコメント一覧を開く
oページを開く