mysql - perl 中 DBD 和 mysql 的问题

Question

拜托，我已经尝试了好几个小时，无法追踪这段代码的问题。它给我错误 DBD::mysql::st fetchrow_hashref failed: fetch() without execute() at line 15

        sub Split_Into_Words
        {
            #### Connection parameters ############################
            my $dsn =  "dbi:mysql:malware:localhost:3306";
            my $user = 'root';
            my $passwd = 'sxxxs';
            ########################################################
            my $domain ;
            my $countDir = 0 ;
            my $file = shift ;
            my $labelID  =  (split(/[.]/ , $file))[1] ; ### Split and get the middle value since format is temporay.

            #### Query String ############################################################################
             my $InsertIntoHostTable_QS  = "INSERT INTO TB_host(HostName  , UrlID , ExtID) Values (? , ? , ? ) ; ";
             my $InsertIntoDomainTable_QS = "INSERT IGNORE INTO  TB_Domain(Domain) values (?) ;" ;
             my $InsertIntoArgVal_QS = "INSERT INTO TB_Arg_Value(Arg, URL_ID)  VALUES (?  , ? ) ; " ; 
             my $InsertIntoDirectory_QS = "INSERT INTO TB_Directory(DIRNAME , DEPTH , URLID) VALUES (? , ? , ? )" ;
             my $InsertIntoExtension_QS = "INSERT IGNORE INTO TB_Extension (Extension) values ( ? ) ; ";
             my $InsertIntoExtensionNULL_QS =   "INSERT IGNORE INTO TB_Extension (ID , Extension) values (? , ? )  ; ";
             my $SelectString  = " Select URL , ID  from TB_URL where LabelID = '"  .  $labelID."';";
             my $InsertIntoFileName_QS  = "INSERT IGNORE INTO TB_FileName( filename)  VALUES (?) ; " ; 

             ###################################################################################################
             my $DBIConnect = DBI->connect($dsn , $user , $passwd) or die("Cannot connect to datadbase  $DBI::errstr\n");   


            print ("Splitting Into Words \n");


            ######Initialization of a default DB value #################
            my $sth =  $DBIConnect->prepare( $InsertIntoExtensionNULL_QS);
                    $sth->execute(1 , 'null') or die("Error Executing the Insertion" . $sth->errstr );
                    $sth->finish();
            #############################################################
            $sth =  $DBIConnect ->prepare($SelectString);
            sleep(10);
            open (FH , '<' , $file); # Open file to be read from disk

            my $i = 0;
            $sth->execute() or die("Error Executing the Insertion" . $sth->errstr );

   ->line 15        while(my $hash_ref = $sth->fetchrow_hashref )
            {
                    my $extensionID = "1";
                    my $intialURL =  $hash_ref->{URL} ;

                my $initialID = $hash_ref->{ID};
    }
    }

Answer 1

我不确定这是否是问题所在，但您可能不需要在插入后完成。来自DBI doc :

Indicate that no more data will be fetched from this statement handle before it is either executed again or destroyed. You almost certainly do not need to call this method.

Adding calls to finish after loop that fetches all rows is a common mistake, don't do it, it can mask genuine problems like uncaught fetch errors.

如果这是问题所在，您可能需要为 select 调用创建第二个语句处理程序。