如何將散列傳遞給子？

Question

在我的Perl腳本中，我正在收集數據並構建一個hashmap。 hashmap鍵表示字段名稱，值表示我想要插入到相應字段中的值。

構建hashmap，然後傳遞給saveRecord（）方法，該方法應該構建SQL查詢並最終執行它。

這裏的想法是更新數據庫一次，而不是每個字段一次（有很多字段）。

問題：我無法將散列圖傳遞給sub，然後將字段和值從散列表中提取出來。在這一點上，我的鍵和值是空白的。我懷疑數據在傳遞給一個子組的過程中正在丟失。

該腳本的輸出指示沒有鍵和沒有值。

需要幫助將數據傳遞給子圖的方式可以讓我將其拉回如圖所示 - 與join()。

謝謝！

代碼片段：

for my $key (keys %oids) { 
     $thisField = $key; 
     $thisOID = $oids{$thisField}; 
     # print "loop: thisoid=$thisOID field=$thisField\n"; 

     # perform the SNMP query. 
     $result = getOID ($thisOID); 
     # extract the information from the result. 
     $thisResult = $result->{$thisOID}; 

     # remove quotation marks from the data value, replace them with question marks. 
     $thisResult =~ s/\"|\'|/\?/g; 

     # TODO: instead of printing this information, pass it to a subroutine which writes it to the database (use an update statement). 
     # printf "The $thisField for host '%s' is '%s'.\n", $session->hostname(), $result->{$thisOID}; 

     # add this key/value pair to the mydata hashmap. 
     $mydata{$thisField} = $thisResult; 

     # print "$thisField=$thisResult\n"; 
} 


# write one record update for hashmap %mydata. 
saveRecord (%mydata); 


# write all fields to database at once... 
sub saveRecord ($) { 
     my $refToFields=shift; 


     my @fieldlist = keys %$refToFields; 
     my @valuelist = values %$refToFields; 
     my $sql = sprintf ("INSERT INTO mytable (%s) VALUES (%s)",join(",",@fieldlist), join(",",@valuelist)); 

     # Get ID of record with this MAC, if available, so we can perform SQL update 
     my $recid = getidbymac ($MAC); 

     print "sql=$sql\n"; 
    # TODO: use an insert or an update based on whether recid was available... 
     # TODO: ID available, update the record 
     # TODO: ID not available, insert record let ID be auto assigned. 
} 

Answer 1

我清理你的一些代碼。打電話給您的小組時，您的主要問題是沒有使用參考。另外要注意的評論正則表達式這是清理：

代碼：

use strict; 
use warnings; 

# $thisResult =~ s/["']+/?/g; 
my %mydata = ('field1' => 12, 'field2' => 34,); 

saveRecord (\%mydata); # <-- Note the added backslash 

sub saveRecord { 
    my $ref = shift; 
    my $sql = sprintf "INSERT INTO mytable (%s) VALUES (%s)", 
     join(',', keys %$ref), 
     join(',', values %$ref); 
    print "sql=$sql\n"; 
} 

輸出：

sql=INSERT INTO mytable (field1,field2) VALUES (12,34)