truncate语句，是清空表中的内容，包括自增主键的信息。truncate表后，表的主键就会重新从1开始。(执行此操作表内容将会被全部清空)
语法：

TRUNCATE TABLE table1;

TRUNCATE TABLE adclicks;
TRUNCATE TABLE adminpanel;
TRUNCATE TABLE advertisements;
TRUNCATE TABLE agent_allowed_exception;
TRUNCATE TABLE agent_allowed_family;
TRUNCATE TABLE allowedemails;
TRUNCATE TABLE attachments;
TRUNCATE TABLE attendance;
TRUNCATE TABLE audiocodecs;
TRUNCATE TABLE avps;
TRUNCATE TABLE bannedemails;
TRUNCATE TABLE bans;
TRUNCATE TABLE bitbucket;
TRUNCATE TABLE blocks;
TRUNCATE TABLE bookmarks;
TRUNCATE TABLE categories;
TRUNCATE TABLE caticons;
TRUNCATE TABLE cheaters;
TRUNCATE TABLE chronicle;
TRUNCATE TABLE codecs;
TRUNCATE TABLE comments;
TRUNCATE TABLE complains;
TRUNCATE TABLE complain_replies;
TRUNCATE TABLE countries;
TRUNCATE TABLE downloadspeed;
TRUNCATE TABLE faq;
TRUNCATE TABLE files;
TRUNCATE TABLE forummods;
TRUNCATE TABLE forums;
TRUNCATE TABLE friends;
TRUNCATE TABLE fun;
TRUNCATE TABLE funds;
TRUNCATE TABLE funvotes;
TRUNCATE TABLE invites;
TRUNCATE TABLE iplog;
TRUNCATE TABLE iplog_announce;
TRUNCATE TABLE isp;
TRUNCATE TABLE language;
TRUNCATE TABLE links;
TRUNCATE TABLE locations;
TRUNCATE TABLE loginattempts;
TRUNCATE TABLE magic;
TRUNCATE TABLE media;
TRUNCATE TABLE messages;
TRUNCATE TABLE modpanel;
TRUNCATE TABLE news;
TRUNCATE TABLE offers;
TRUNCATE TABLE offervotes;
TRUNCATE TABLE overforums;
TRUNCATE TABLE peers;
TRUNCATE TABLE pmboxes;
TRUNCATE TABLE pollanswers;
TRUNCATE TABLE polls;
TRUNCATE TABLE posts;
TRUNCATE TABLE processings;
TRUNCATE TABLE prolinkclicks;
TRUNCATE TABLE readposts;
TRUNCATE TABLE regimages;
TRUNCATE TABLE reports;
TRUNCATE TABLE rules;
TRUNCATE TABLE schools;
TRUNCATE TABLE searchbox;
TRUNCATE TABLE secondicons;
TRUNCATE TABLE shoutbox;
TRUNCATE TABLE sitelog;
TRUNCATE TABLE snatched;
TRUNCATE TABLE sources;
TRUNCATE TABLE staffmessages;
TRUNCATE TABLE standards;
TRUNCATE TABLE stylesheets;
TRUNCATE TABLE subs;
TRUNCATE TABLE suggest;
TRUNCATE TABLE sysoppanel;
TRUNCATE TABLE teams;
TRUNCATE TABLE thanks;
TRUNCATE TABLE topics;
TRUNCATE TABLE torrents;
TRUNCATE TABLE torrents_myrss;
TRUNCATE TABLE torrents_state;
TRUNCATE TABLE uploadspeed;
TRUNCATE TABLE users;
TRUNCATE TABLE user_invitations;