HandlerSocket的perl接口操作方法

实例化：

$hs = new HandlerSocket($host,$port);

运用例子:

#9998为读取端口 详见上一篇handlersocket的安装

my $args = { host => 'localhost',port => 9998 };  
my $hs = new Net::HandlerSocket($args); 

$hs->openIndex($index,$dbname,$table,$key,$column);

运用例子:

 my $res = $hs->open_index(0,'test','user','PRIMARY','user_name,user_email,created'); ? 
  die $hs->get_error() if $res != 0;  


 #打开test数据的user表 以主键为key
 #这个为查询的列数，这里为三列，分别为：user_name,created

$retval = $hs->executeSingle($index,$operation,$value,$number,$skip); 

运用例子:

my $args = { host => 'localhost',port => 9998 };  
my $hs = new Net::HandlerSocket($args);  
    
my $res = $hs->open_index(0,created'); 
die $hs->get_error() if $res != 0;   

$res = $hs->execute_single(0,[ 1 ],2,0);   # 此查询语句的意思是：查询主键大于或等于1，数据取2行

die $hs->get_error() if $res->[0] != 0;  
shift(@$res); 

# 这里我们要注意：execute_single方法的返回值类型为arrayref，其第一个元素为error code：如果为0，则为正常，否则不正常，数组从第

二元素开始即为返回的值，存储格式为 后面一行紧跟前面一行！
 

#下面为分行打印这个数组的所有值
for (my $row = 0; $row <2 ; ++$row) {  
    my $user_name= $res->[$row + 0];  
    my $user_email= $res->[$row+ 1];  
    my $created= $res->[$row + 2];  
if ($user_name || $user_email || $created)
{
    print "$user_namet$user_emailt$createdn";  
}
else
{ last; 
}

}  
 
  $hs->close();

$retval = $hs->execute_single(3,'+',[5,'zhongguo','zhogonguo@email.com','2011-01-08 13:51:33' ],1,0);

运用例子:

my $args = { host => 'localhost',port => 9999 };  
my $hs = new Net::HandlerSocket($args); 


my $res = $hs->open_index(3,'user_id,user_name,created');  
die $hs->get_error() if $res != 0;

$res = $hs->execute_single(3,0);  
die $hs->get_error() if $res->[0] != 0;  
 $hs->close();

$retval = $hs->executeDelete($index,$skip);

运用例子:

my $args = { host => 'localhost',port => 9999 };  
my $hs = new Net::HandlerSocket($args);  
my $res = $hs->open_index(3,'user_name');  
die $hs->get_error() if $res != 0; 
$res = $hs->execute_single(3,'=',[4],'D'); #DELETE user_id=4 的数据
print $res;
die $hs->get_error() if $res != 0;
$hs->close();

$retval = $hs->executeUpdate($index,$skip); 

my $args = { host => 'localhost',port => 9999 };  
my $hs = new Net::HandlerSocket($args);  
?
my $res = $hs->open_index(3,'user_name');  
die $hs->get_error() if $res != 0;

$res = $hs->execute_single(3,[5],'U',['woaini']);  #当user_id=5，更新'user_name'为woaini
die $hs->get_error() if $res->[0] != 0;
$hs->close();

my $rarr = $hs->execute_multi([  
  [ 0,[ 'foo' ],5,0 ],[ 2,[ 'bar' ],[ 4,'<',[ 'baz' ],10,5 ],]);  
for my $res (@$rarr) {  
  die $hs->get_error() if $res->[0] != 0;  
  shift(@$res);  
  # ...  
}  

PS：

handlerscoket中有两个 重要的特性;

Write operations do not invalidate the query cache – Exactly what it sounds like,if you performed a write operation via HandlerSocket,you could potentially read stale data from the MySQL interface.

l?写操作并没有淘汰查询缓存?-?如果执行了写操作通过HandlerSocket，由于没有失效查询缓存,那么你可能从MySQL读到旧的数据。??

No support for auto increment – Exactly as it sounds,you couldn’t have auto-incrementing columns get an auto increment value on insert.

l?不支持自动递增?-?插入时无法从自增列上自动获得增量值??

今天 我在测试把同一批数据插入一张数据表两次时 ?发现 插入第一次之后 不能插入第二次了 ?找了很久原因 看到第二个特性之后才想起 ?我们每次 openindex的时候都是要用到主键的 ?如果 这里 你要插入的数据的主键 已经存在数据库中了 ?就会报 121的错误。