随着业务量的增长，可能需要对表进行拆分来提高性能。
下面这个例子是将www.jb51.net的users表拆分成10个表ttlsa_user_0-ttlsa_user_9。
拆分迁移数据程序如下所示：
1.创建ttlsa_user_0-ttlsa_user_9表
use DBI;
my $driver=”DBI:mysql”;
my $from_database=”ttlsa”;
my $from_user=”root”;
my $from_password=”123456″;
my $from_host=”localhost”;
$from_dbh=DBI->connect (“$driver:$from_database:$from_host;user=$from_user;password=$from_password”) or die “cannot connect: “. DBI->errstr;
for (0..9) {
$sql=”CREATE TABLE `ttlsa_user_$_` (
`uid` int(10) NOT NULL AUTO_INCREMENT,
`email` varchar(50) NOT NULL,
`passwd` varchar(40) NOT NULL,
`user_name` varchar(20) NOT NULL,
PRIMARY KEY (`uid`),
UNIQUE KEY `email` (`email`),
UNIQUE KEY `user_name` (`user_name`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 ROW_FORMAT=COMPACT”;
$from_dbh->do($sql);
}
$from_dbh->disconnect();
2.迁移数据
use DBI;
my $driver=”DBI:mysql”;
my $from_database=”ttlsa”;
my $from_user=”root”;
my $from_password=”123456″;
my $from_host=”localhost”;
$from_dbh=DBI->connect (“$driver:$from_database:$from_host;user=$from_user;password=$from_password”) or die “cannot connect: “. DBI->errstr;
$from_dbh->do(“set names ‘utf8′”);
$from_dbh->do(“set session autocommit=0″);
$from_dbh->do(“set session unique_checks=0″);
$max=600000;
$step=10000;
for ($i=1;$i $step_i=$i+$step;
$sql=”select * from ttlsa_users where user_id>=$i and user_id $sth=$from_dbh->prepare($sql);
$sth->execute;
@value=();
while ($row=$sth->fetchrow_hashref()) {
$uid=$row->{uid};
$email=$row->{email};
$passwd=$row->{passwd};
$user_name=$row->{user_name};
$key=substr($user_id,-1);
$value[$key].=”(‘$uid','$email','$passwd','$user_name'),”;
}
for (0..9) {
chop($value[$_]);
$sql=”insert into ttlsa_user_$_ (`uid`,`email`,`passwd`,`user_name`) values” . $value[$_];
$from_dbh->do(“$sql”);
}
}
$from_dbh->do(“set session autocommit=1″);
$from_dbh->do(“set session unique_checks=1″);
$sth->finish();
$from_dbh->disconnect();
3.附录
如果没有那么多数据量，可以随意插入一些数据进行测试。下面提供一个插入数据的脚本。
use DBI;
use Digest::SHA qw(sha1_hex);
my $driver=”DBI:mysql”;
my $from_database=”ttlsa”;
my $from_user=”root”;
my $from_password=”123456″;
my $from_host=”localhost”;
$from_dbh=DBI->connect (“$driver:$from_database:$from_host;user=$from_user;password=$from_password”) or die “cannot connect: “. DBI->errstr;
$from_dbh->do(“set names ‘utf8′”);
$from_dbh->do(“set session autocommit=0″);
$from_dbh->do(“set session unique_checks=0″);
for (1..100000) {
$insert_sql=$from_dbh->prepare(“insert into ttlsa_users (email,passwd,user_name) values (?,?,?)”);
$email=”auto-gre-$_\@jb51.net”;
$data=”auto-gre-$_”;
$passwd=sha1_hex($data);
$user_name=”auto-gre-$_”;
$insert_sql->execute($email,$passwd,$user_name);
}
$from_dbh->do(“set session autocommit=1″);
$from_dbh->do(“set session unique_checks=1″);
$insert_sql->finish();
$from_dbh->disconnect();
