[perl] 连接mysql

先写在这里吧，之后再改进~~

package mysql_conn;
use DBI;
use strict;
sub new{
 my $class = shift();
 print ("CLASS=$class\n");
 my $self={};
 $self->{"location"} = shift();
 $self->{"db_name"} = shift();
 $self->{"db_user"} = shift();
 $self->{"db_pass"} = shift();
 bless $self,$class;
 return $self;
}
sub get_table_flag_1_3{
 my ($self,$TABLE)=@_;
 my $port = "3306"; #这是mysql的缺省
 my $location=$self->{"location"};
 my $db_name=$self->{"db_name"};
 my $db_user = $self->{"db_user"};
 my $db_pass = $self->{"db_pass"};
 my $database = "DBI:mysql:$dbname:$location:$port";
 my $dbh = DBI->connect($database,$db_user,$db_pass) or die "Cann‘t connect the Database".DBI->errstr;
 my $sql = "SELECT file,owner FROM TABLE where flag=1 or flag=3";
 my $sth = $dbh->prepare($sql);
 my $result=$sth->execute() or die "db operation Error:$dbh->errstr"; #执行
 $sth->finish();
 $dbh->disconnect;#断开数据库连接
 return $result;
}

1. ##------------------------------------------------------------------------------------------------
   
2. ##利用perl DBI创建数据库stucourse,并创建student,course,grade表
   
3. ##------------------------------------------------------------------------------------------------
   
4. use DBI;
   
5. my $db_name = "stucourse"; #数据库名,如果与现有数据库冲突，可改为其他名字
   
6. my $db_host = "localhost"; #主机名
   
7. my $db_port = ‘3306‘; #端口号
   
8. my $username = "root"; #用户名
   
9. my $password = "123"; #密码
   
10. my $dsn = "dbi:mysql:database=${db_name};hostname=${db_host};port=${db_port}";#数据源
    
11. 
    
12. #获取驱动程序对象句柄
    
13. my $drh=DBI->install_driver("mysql"); 
    
14. #如果存在数据库$db_name,则删除之
    
15. if($rc = $drh->func("dropdb",$db_name ,$db_host,$username,$password,"admin") ){ 
    
16.     print "drop database `",$db_name,"` successfully!\n";
    
17. }
    
18. #创建数据库$db_name
    
19. $rc = $drh->func("createdb",$db_name ,$db_host,$username,$password,"admin")or
    
20.     die "failed to create database ",$db_name,"!\n";
    
21. print "create database `stucourse` successfully!\n";
    
22. 
    
23. #获取数据库句柄
    
24. my $dbh = DBI -> connect ($dsn, $username, $password,{RaiseError => 1, PrintError => 0})or
    
25.     die "failed to connect to the database!\n",DBI->errstr();
    
26. 
    
27. #设置数据库字符集，防止中文乱码
    
28. my $charset = "set character_set_database=utf8";
    
29. my $sth = $dbh->prepare($charset);
    
30. $sth->execute();
    
31. 
    
32. #创建表course
    
33. my $query = "CREATE TABLE `course` ( "
    
34.             ."`cid` int(10) NOT NULL auto_increment,"
    
35.             ."`cno` varchar(20) NOT NULL, "
    
36.             ."`cname` varchar(20) default NULL, "
    
37.             ."PRIMARY KEY (`cid`)" 
    
38.             .")ENGINE=InnoDB DEFAULT CHARSET=utf8;";
    
39. my $sth = $dbh->prepare($query);
    
40. $sth->execute() or die "create table course error: ".$sth->errstr();
    
41. print "create table `course` successfully!\n";
    
42. 
    
43. #创建表student
    
44. my $query = "CREATE TABLE `student` ("
    
45.             ."`sid` int(10) NOT NULL auto_increment,"
    
46.             ."`sno` varchar(20) NOT NULL,"
    
47.             ."`sname` varchar(20) default NULL,"
    
48.             ."PRIMARY KEY (`sid`)"
    
49.             .")ENGINE=InnoDB DEFAULT CHARSET=utf8;";
    
50. my $sth = $dbh->prepare($query);
    
51. $sth->execute() or die "create table student error: ".$sth->errstr();
    
52. print "create table `student` successfully!\n";
    
53. 
    
54. #创建表grade
    
55. my $query = "CREATE TABLE `grade` ("
    
56.          ."`gid` int(10) NOT NULL,"
    
57.          ."`cid` int(10) NOT NULL,"
    
58.          ."`sid` int(10) NOT NULL,"
    
59.          ."`grade` int(10) default NULL,"
    
60.          ."PRIMARY KEY (`gid`),"
    
61.          ."KEY `cid` (`cid`),"
    
62.          ."KEY `sid` (`sid`),"
    
63.          ."CONSTRAINT `cid` FOREIGN KEY (`cid`) REFERENCES `course`(`cid`),"
    
64.          ."CONSTRAINT `sid` FOREIGN KEY (`sid`) REFERENCES `student`(`sid`)"
    
65.          .") ENGINE=InnoDB DEFAULT CHARSET=utf8;";
    
66. my $sth = $dbh->prepare($query);
    
67. $sth->execute() or die "create table grade error: ".$sth->errstr();
    
68. print "create table `grade` successfully!\n";
    
69. 
    
70. #关闭数据库连接
    
71. $dbh->disconnect();

fetchrow_array ()抽取方法的返回是一个包含查询结果的数组。还有其它方法：

fetchrow_arrayref ()返回一个数组引用。

fetchrow_hashref ()返回散列引用。

原文：http://my.oschina.net/u/347414/blog/353937