DBI – Perl – 记录MySQL警告

Perl 前端之家
前端之家收集整理的这篇文章主要介绍了DBI – Perl – 记录MySQL警告，前端之家小编觉得挺不错的，现在分享给大家，也给大家做个参考。
我正在使用DBI并希望将 MySQL WARNINGS的日志记录添加到此脚本中.我能够毫无问题地记录真正的MysqL错误,但此时我需要追踪正在生成的MysqL警告.如果MysqL语句失败,我可以将错误的sql语句打印到bad_sql.txt并自动生成一封电子邮件.我需要进行两次更改,而且我真的卡住了
1)如果语句执行但有一个MysqL警告我想将其捕获到last_sql_warning.txt
2)如果语句错误导致锁定超时,我想重新提交查询两次.

这就是现在被转储到日志中的内容.

MiscLibs :: MysqL :: MysqLDoCmd,MysqL.pm第564行：
– > UPDATE tbl_xxx_files SET ReloadStart = 123“WHERE(FileName =”image.txt“)< - 相关的代码块 

#=====================================================================================
# Execute MysqL commands and handle errors
#=====================================================================================

sub MysqLDoCmd ($;$) {

my ($MysqLCmd,$Quite) = @_;

 if ( eval { $DBHandle->do($MysqLCmd) } ) {
   open (MYFILE2,'>/bb/bin/fa/logs/last_sql_warning.txt');
   # trying to write warning to log.  As a first pass I was attempting to write 
   # each statement to the log and include any warnings.  What I would like code to
   # do is check if there is a warning and only then write that statement to the log. 

   print MYFILE2 MysqLMakeID() . ": $DBHandle->errstr\n-->$MysqLCmd<--\n";

return 0;

} elsif ( ! $Quite ) {
  open (MYFILE,'>>/bb/bin/fa/logs/badsql.txt');
  print MYFILE  MysqLMakeID() . ": $@\n-->$MysqLCmd<--\n";

#=========SENDS EMAIL ON STATEMENT FAILURE===================
 while (my ($addressee,$address) = each (%emailList))
 {
     print STDERR "INFO: Sending email to $addressee at address $address\n";
     $message =~ s/ADDRESSEE/$addressee/g;
     $message =~ s/ERRORREASON/$errMessage/g;
     &sendMail($addressee,$address,$message);
     $message =~ s/$addressee/ADDRESSEE/g;
     $message =~ s/$errMessage/ERRORREASON/g;
  }

return 1;

 } else {
  return 1;

 }

}

完整的代码块

use strict;                        # Everything must be defined before it is used
use warnings;                      # Print warnings
use POSIX;                         # Provides POSIX functions
use English '-no_match_vars';      # Provides access to English version of builtin variables
use Net::SMTP;

#===================================================================================================

package MiscLibs::MysqL;
use Exporter ();

our ($VERSION,@ISA,@EXPORT,@EXPORT_OK);

$VERSION = '1.00';
@ISA = qw(Exporter);
@EXPORT_OK = ( );
@EXPORT = qw( 

MysqLOpenConnection
MysqLCloseConnection

MysqLCloseHandle

MysqLErrNo
MysqLError
MysqLHostInfo
MysqLInfo
MysqLInsertID
MysqLProtoInfo
MysqLServerInfo
MysqLStat
MysqLThreadID
MysqLDBDStats
MysqLAutoReconnect
MysqLUseResult
MysqLShowTables
MysqLShowColumns
MysqLValidateFields
MysqLNumOfFields
MysqLErrStr
MysqLUseResults

MysqLDoCmd

MysqLDeleteRows
MysqLDeleteRowsICS
MysqLInsertRow
MysqLUpdateRows

MysqLSelectRows
MysqLGetHashRef
MysqLGetArray
MysqLSetLastUpdate
MysqLSetReportState

MysqLTruncateTable
MysqLDisableKeys
MysqLEnableKeys
MysqLOptimizeTable

MysqLCacheAddTable
MysqLCacheAddBuffer
MysqLCacheFlush

);
#=====================================================================================
my %emailList = (
                   "bob"=>"\@bog.com",);

my $errMessage = "error_message";
my $message = "MysqL Query Timed out - check logs/";

#======================================================================================
 sub sendMail()
{
 #not relevant - smtp code

     print "EXECUTE: Mail sent successfully\n";
}

#======================================================================================

use File::Basename;                # Provides basename,dirname and fileparse functions
use Data::Dumper;
use DBI;                           # Interface to MysqL

my $DBHandle;

my %CacheFieldNameStrings;
my %CacheFieldNameArrays;
my %CacheSizes;
my %CacheFieldValues;
my %CacheDupKeyCmds;

my %ValidateFieldNames;

my $MaxCacheSize = 50;

1;

#=====================================================================================
# Create an ID string for error reporting
#=====================================================================================

sub MysqLMakeID {

  my ($package,$filepath,$line,$subroutine,$hasargs,$wantarray,$evaltext,$is_require,$hints,$bitmask) = caller(1);

  $subroutine =~ s/main:://;

  my $filename = basename($filepath);

  my $id = "$subroutine,$filename line $line";

  # print "ID: '$id'\n";

  return $id;

}

#=====================================================================================
# Open MysqL connection and get reference information
#=====================================================================================

sub MysqLOpenConnection (;$) {

  my ( $NewMaxCacheSize ) = @_;

  my $Database;
  my $Host;
  my $Port;
  my $DSN;
  my $User;
  my $Password;
  my %Options;

  if ( defined($NewMaxCacheSize) && ($NewMaxCacheSize > 1) ) { $MaxCacheSize = $NewMaxCacheSize }

  $Database = $ENV{MysqLDatabase}; if ( ! defined($Database) ) { $Database = "database" }
  $Host     = $ENV{MysqLHost};     if ( ! defined($Host)     ) { $Host     = "host" }
  $Port     = $ENV{MysqLPort};     if ( ! defined($Port)     ) { $Port     = 123 }

  $DSN = "DBI:MysqL";
  $DSN = $DSN . ":$Database";
  $DSN = $DSN . ";host=$Host";
  $DSN = $DSN . ";port=$Port";
  $DSN = $DSN . ";MysqL_compression=1";

  $User     = 'user';
  $Password = 'pw';

  %Options = ( RaiseError => 1 );

  $DBHandle = DBI->connect($DSN,$User,$Password,\%Options);

  return $DBHandle;

}

#=====================================================================================
# Close MysqL connection opened above or a handle that is passed
#=====================================================================================

sub MysqLCloseConnection {
  if ( $DBHandle ) { $DBHandle->disconnect }
  return 0;
}

sub MysqLCloseHandle ($) { 
  my ($sh) = @_;
  if ( $sh ) { $sh->finish() }
  return 0;
}

#=====================================================================================
# Return a varIoUs database handle values and conditions
#=====================================================================================

sub MysqLErrNo      () { return $DBHandle->{'MysqL_errno'}      }
sub MysqLError      () { return $DBHandle->{'MysqL_error'}      }
sub MysqLHostInfo   () { return $DBHandle->{'MysqL_hostinfo'}   }
sub MysqLInfo       () { return $DBHandle->{'MysqL_info'}       }
sub MysqLInsertID   () { return $DBHandle->{'MysqL_insertid'}   }
sub MysqLProtoInfo  () { return $DBHandle->{'MysqL_protoinfo'}  }
sub MysqLServerInfo () { return $DBHandle->{'MysqL_serverinfo'} }
sub MysqLStat       () { return $DBHandle->{'MysqL_stat'}       }
sub MysqLThreadID   () { return $DBHandle->{'MysqL_thread_id'}  }
sub MysqLDBDStats   () { return $DBHandle->{'MysqL_dbd_stats'}  }

#=====================================================================================
# Optionally set but always return varIoUs database handle values and conditions
#=====================================================================================

sub MysqLAutoReconnect (;$) { 
  my $val = $_[0];
  if ( defined($val) ) { $DBHandle->{'MysqL_auto_reconnect'} = $val }
  return $DBHandle->{'MysqL_auto_reconnect'};
}

sub MysqLUseResult (;$) { 
  my $val = $_[0];
  if ( defined($val) ) { $DBHandle->{'MysqL_use_result'} = $val }
  return $DBHandle->{'MysqL_use_result'};
}

#=====================================================================================
# Execute MysqL commands and handle errors
#=====================================================================================

sub MysqLDoCmd ($;$) {

  my ($MysqLCmd,$Quite) = @_;

  if ( eval { $DBHandle->do($MysqLCmd) } ) {
       open (MYFILE2,'>>/bb/bin/fa/logs/last_sql.txt');
       #!!!!! trying to write warning to log 
       print MYFILE2 MysqLMakeID() . ": $DBHandle->errstr\n-->$MysqLCmd<--\n";
      return 0;

  } elsif ( ! $Quite ) {
      open (MYFILE,'>>/bb/bin/fa/logs/badsql.txt');
      print MYFILE  MysqLMakeID() . ": $@\n-->$MysqLCmd<--\n";

#=========SENDS EMAIL ON STATEMENT FAILURE===================    
 while (my ($addressee,$address) = each (%emailList))
     {
         print STDERR "INFO: Sending email to $addressee at address $address\n";
         $message =~ s/ADDRESSEE/$addressee/g;
         $message =~ s/ERRORREASON/$errMessage/g;
         &sendMail($addressee,$message);
         $message =~ s/$addressee/ADDRESSEE/g;
         $message =~ s/$errMessage/ERRORREASON/g;
      }

    return 1;

  } else {
    return 1;

  }

}

#=====================================================================================
# Delete rows from a MysqL table
#=====================================================================================

sub MysqLDeleteRows ($;$) {

  my ($Table,$WhereRef) = @_;

  my $WhereList;

  my $MysqLCmd = 'DELETE FROM ' . $Table;

  if ( $WhereRef ) {
    $WhereList = BuildLists ('where',$WhereRef);
    $MysqLCmd = $MysqLCmd . $WhereList;
  }

  return MysqLDoCmd($MysqLCmd);

}


#=====================================================================================
# Select rows from a MysqL table and return a statement handle
#=====================================================================================

sub MysqLSelectRows ($$;$$) {

  my ($What,$Table,$WhereRef,$OrderRef) = @_;

  my $MysqLCmd = "SELECT $What FROM $Table";

  if ( $WhereRef ) { $MysqLCmd = $MysqLCmd . BuildLists ('Where',$WhereRef) }
  if ( $OrderRef ) { $MysqLCmd = $MysqLCmd . BuildLists ('OrderBy',$OrderRef) }

  # print "MysqLSelectRows: MysqLCmd '$MysqLCmd'\n";

  my $StmtHandle;

  if ( ! eval {  $StmtHandle = $DBHandle->prepare($MysqLCmd) } ) {
    print STDERR MysqLMakeID() . ": $@\n-->$MysqLCmd<--\n";
    return undef;

  } elsif ( ! eval { $StmtHandle->execute() } ) {
    print STDERR MysqLMakeID() . ": $StmtHandle->errstr\n-->$MysqLCmd<--\n";
    return undef;

  } else {
    return $StmtHandle;

  }

}

#=====================================================================================
# Return a varIoUs statement handle values and conditions
#====================================================================================

sub MysqLNumOfFields ($) { my ($sh) = @_; return $sh->{'NUM_OF_FIELDS'}      }
sub MysqLErrStr      ($) { my ($sh) = @_; return $sh->errstr                 }

sub MysqLGetHashRef  ($) { my ($sh) = @_;
  if ( my $Ref = $sh->fetchrow_hashref() ) { return $Ref }
  else                                     { MysqLCloseHandle($sh); return undef } 
}

sub MysqLGetArray ($) { my ($sh) = @_; 
  if ( my $Ref = $sh->fetchrow_array()   ) { return $Ref }
  else                                     { MysqLCloseHandle($sh); return undef } 
}

#=====================================================================================
# Optionally set but always return varIoUs statement handle values and conditions
#=====================================================================================

sub MysqLUseResults ($;$) { 
  my ($sh,$val) = @_;
  if ( defined($val) ) { $sh->{'MysqL_use_result'} = $val }
  return $sh->{'MysqL_use_result'};
}

#=====================================================================================
# Update a row in a MysqL table
#=====================================================================================

sub MysqLUpdateRows ($$;$) {

  my ($Table,$SetRef,$WhereRef) = @_;

  my $MysqLCmd;
  my $SetList;
  my $WhereList;

  $MysqLCmd = 'UPDATE ' . $Table;

  $SetList = BuildLists ('set',$SetRef);

  $MysqLCmd = $MysqLCmd . $SetList;

  if ( $WhereRef ) {
    $WhereList = BuildLists ('where',$WhereRef);
    $MysqLCmd = $MysqLCmd . $WhereList ;
  }

  # print "MysqLUpdateRows: MysqLCmd '$MysqLCmd'\n";

  return MysqLDoCmd($MysqLCmd);

}



#=====================================================================================
# Truncate a MysqL table
#=====================================================================================

sub MysqLTruncateTable ($) {

  my ($Table) = @_;

  my $MysqLCmd = 'TRUNCATE TABLE ' . $Table;

  return MysqLDoCmd($MysqLCmd);

}




#=====================================================================================
#
# The routines below maintain a cache of MysqL values to allow inserting multiple
# rows at a time to improve efficiency
#
#=====================================================================================

#=====================================================================================
# Add a table to the MysqL Cache
#=====================================================================================

sub MysqLCacheAddTable ($$;$) {

  my ( $TableName,$FieldNameArray,$DupKeyCmds ) = @_;

  my $DupKeyCmd;

  my $FieldName;
  my $FieldNameString = '';

  for $FieldName ( @$FieldNameArray ) {
    if ( $FieldNameString ) { $FieldNameString = $FieldNameString . ',' }
    $FieldNameString = $FieldNameString . $FieldName;    
  }

    $CacheFieldNameStrings{$TableName} = $FieldNameString;
  @{$CacheFieldNameArrays{$TableName}} = @$FieldNameArray;
  $CacheDupKeyCmds{$TableName}         = $DupKeyCmds;
  $CacheSizes{$TableName}              = 0;
  $CacheFieldValues{$TableName}        = '';

  return 0;

}

#=====================================================================================
# Add a buffer to the MysqL cache
#=====================================================================================

sub MysqLCacheAddBuffer ($$) {

  my ( $TableName,$AddValues ) = @_;

  my $FieldName;
  my $FieldValue;
  my $FieldValues;

  my $CacheValues;

  if ( ! defined($CacheFieldNameStrings{$TableName}) ) {
    print STDERR MysqLMakeID() . ": Table '$TableName' has not been initialized with the 'AddTable' command\n"; 
    return 1;
  }

  if ( $CacheSizes{$TableName} >= $MaxCacheSize ) { 
    # if ( $TableName eq 'tbl_xyz' ) {
      # print "Flushing $TableName cache before adding buffer: CacheSize = '$CacheSizes{$TableName}'\n" }
    MysqLCacheFlush ($TableName);
  }

  $FieldValues = '';

  for $FieldName ( @{$CacheFieldNameArrays{$TableName}} ) {

    $FieldValue = $AddValues->{$FieldName};

    if ( ! defined($FieldValue) ) { $FieldValue  =  '' }                 # Make sure value is defined
    else                          { $FieldValue  =~ s/(["',\\])/\\$1/g } # Make sure that MysqL special chars are escaped

    if ( $FieldValues ) { $FieldValues =  $FieldValues . "," }

    $FieldValues =  $FieldValues . "'" . $FieldValue . "'";

  }

  $CacheValues = $CacheFieldValues{$TableName};

  if ( $CacheValues ) { $CacheValues = $CacheValues . ',' }

  $CacheValues = $CacheValues . '(' . $FieldValues . ')';

  $CacheFieldValues{$TableName} = $CacheValues;

  $CacheSizes{$TableName}++;

  # if ( $TableName eq 'tbl_xyz' ) {
    # print "Added buffer to $TableName cache: CacheSizes '$CacheSizes{$TableName}',CacheValues '$CacheValues'\n" }

  return 0;

}

#=====================================================================================
# Flush entries from MysqL cache
#=====================================================================================

sub MysqLCacheFlush ($) {

  my ( $TableName ) = @_;

  my $FlushTable;
  my @FlushTables,my $FieldNames;
  my $FieldValues;
  my $DupKeyCmd;

  my $MysqLCmd;

  if ( lc($TableName) eq 'all' ) { 
    for $FlushTable ( keys(%CacheFieldNameStrings) ) { push @FlushTables,$FlushTable }

  } elsif ( ! defined($CacheFieldNameStrings{$TableName}) ) {
    print STDERR MysqLMakeID() . ": Table '$TableName' has not been initialized with the 'AddTable' command\n"; 
    return 1;

  } else {
    push @FlushTables,$TableName;

  }

  FlushTable: for $FlushTable ( @FlushTables ) {

    $FieldValues = $CacheFieldValues{$FlushTable};

    $CacheFieldValues{$FlushTable} = '';
    $CacheSizes{$FlushTable}       = 0;

    if ( ! $FieldValues ) { next FlushTable }

    $FieldNames = $CacheFieldNameStrings{$FlushTable};
    $DupKeyCmd  = $CacheDupKeyCmds{$FlushTable};

#Removed DELAYED after moving to innodb
#$MysqLCmd = "INSERT DELAYED INTO $FlushTable ($FieldNames) VALUES $FieldValues";

 $MysqLCmd = "INSERT INTO $FlushTable ($FieldNames) VALUES $FieldValues";

    if ( $DupKeyCmd ) { $MysqLCmd = $MysqLCmd . ' ON DUPLICATE KEY UPDATE ' . $DupKeyCmd }

    return MysqLDoCmd($MysqLCmd);

  }

}

sub BuildLists ($$;$) {

  my ($Type,$Ref1,$Ref2) = @_;

  my $Ref1Type = ref($Ref1);
  my $Ref2Type = ref($Ref2);

  my $Name;
  my $NameList;
  my $Value;
  my $ValueList;

  my %Fields;

  my $RtnVal;

  $Type = lc($Type);

  my $TypeIndex = index('values set where orderby',$Type);

  # print "Type '$Type',TypeIndex '$TypeIndex',Ref1Type '$Ref1Type',Ref1 '$Ref1'\n";

  if ( $TypeIndex < 0 ) {

    print STDERR MysqLMakeID() . ": $Type is not a a valid type. Use 'values','set' or 'where'\n";
    return $RtnVal;

  } elsif ( $Ref1Type eq '' ) {

    if ( $Type eq 'values' ) {
      $RtnVal = '(' . $Ref1 . ') VALUES (' . $Ref2 . ')';
    } elsif ( $Type eq 'set' ) {
      $RtnVal = ' SET ' . $Ref1;
    } elsif ( $Type eq 'where' ) {
      $RtnVal = ' WHERE ' . $Ref1;
    } elsif ( $Type eq 'orderby' ) {
      $RtnVal = ' ORDER BY ' . $Ref1;
    }

  } elsif ( $Ref1Type eq 'SCALAR' ) {

    if ( $Type eq 'values' ) {
      $RtnVal = '(' . $$Ref1 . ') VALUES (' . $$Ref2 . ')';
    } elsif ( $Type eq 'set' ) {
      $RtnVal = ' SET ' . $$Ref1;
    } elsif ( $Type eq 'where' ) {
      $RtnVal = ' WHERE ' . $$Ref1;    
    } elsif ( $Type eq 'orderby' ) {
      $RtnVal = ' ORDER BY ' . $$Ref1;
    }

  } elsif ( $Ref1Type eq 'HASH' ) {

    for $Name ( keys(%$Ref1) )  {

      $Value = $Ref1->{$Name};

      if ( ! defined($Value) ) { $Value  =  '' }                 # Make sure value is defined
      else                     { $Value  =~ s/(["',\\])/\\$1/g } # Make sure that MysqL special chars are escaped

      $Fields{$Name} = $Value;

    }

    if ( $Type eq 'values' ) {

      while (($Name,$Value) = each %Fields ) {
        if ( $NameList ) {
          $NameList  = $NameList  . ','  . $Name;
          $ValueList = $ValueList . ',"' . $Value . '"';
        } else {
          $NameList  = $Name;
          $ValueList = '"' . $Value . '"';    
        }
      }

      $RtnVal = " ($NameList) VALUES ($ValueList)";

    } elsif ( $Type eq 'set' ) {
      $RtnVal = '';
      while (($Name,$Value) = each %Fields ) {
        if ( $RtnVal ) { $RtnVal = $RtnVal . ',' }
        $RtnVal = $RtnVal . $Name . '="' . $Value . '"';
      }
      $RtnVal = ' SET ' . $RtnVal;

    } elsif ( $Type eq 'where' ) {
      $RtnVal = '';
      while (($Name,$Value) = each %Fields ) {
        if ( $RtnVal ) { $RtnVal = $RtnVal . ' AND ' }
        $RtnVal = $RtnVal . '(' . $Name . '="' . $Value . '")';
      }
      $RtnVal = ' WHERE ' . $RtnVal;

    }

  } else {

    print STDERR MysqLMakeID() . ": Parameter two is unsupported reference type '$Ref1Type'\n";
    return $RtnVal;

  }

  return $RtnVal;

}

sub BuildListsInt ($$;$) {

  my ($Type,$Ref2) = @_;
  my $Ref1Type = ref($Ref1);
  my $Ref2Type = ref($Ref2);

  my $Name;
  my $NameList;
  my $Value;
  my $ValueList;

  my %Fields;

  my $RtnVal;

  $Type = lc($Type);

  my $TypeIndex = index('values set where orderby','set' or 'where'\n";
    return $RtnVal;

  } elsif ( $Ref1Type eq '' ) {

    if ( $Type eq 'values' ) {
      $RtnVal = '(' . $Ref1 . ') VALUES (' . $Ref2 . ')';
    } elsif ( $Type eq 'set' ) {
      $RtnVal = ' SET ' . $Ref1;
    } elsif ( $Type eq 'where' ) {
      $RtnVal = ' WHERE ' . $Ref1;
    } elsif ( $Type eq 'orderby' ) {
      $RtnVal = ' ORDER BY ' . $Ref1;
    }

  } elsif ( $Ref1Type eq 'SCALAR' ) {

    if ( $Type eq 'values' ) {
      $RtnVal = '(' . $$Ref1 . ') VALUES (' . $$Ref2 . ')';
    } elsif ( $Type eq 'set' ) {
      $RtnVal = ' SET ' . $$Ref1;
    } elsif ( $Type eq 'where' ) {
      $RtnVal = ' WHERE ' . $$Ref1;
    } elsif ( $Type eq 'orderby' ) {
      $RtnVal = ' ORDER BY ' . $$Ref1;
    }

  } elsif ( $Ref1Type eq 'HASH' ) {

    for $Name ( keys(%$Ref1) )  {

      $Value = $Ref1->{$Name};

      if ( ! defined($Value) ) { $Value  =  '' }                 # Make sure value is defined
      else                     { $Value  =~ s/(["',"' . $Value . '"';
        } else {
          $NameList  = $Name;
          $ValueList = '"' . $Value . '"';
        }
      }

      $RtnVal = " ($NameList) VALUES ($ValueList)";

    } elsif ( $Type eq 'set' ) {
      $RtnVal = '';
      while (($Name,$Value) = each %Fields ) {
        if ( $RtnVal ) { $RtnVal = $RtnVal . ' AND ' }
        $RtnVal = $RtnVal . '(' . $Name . '=' . $Value . ')';
      }
      $RtnVal = ' WHERE ' . $RtnVal;

    }

  } else {

    print STDERR MysqLMakeID() . ": Parameter two is unsupported reference type '$Ref1Type'\n";
    return $RtnVal;

  }

  return $RtnVal;

}

解决方法

你问两个问题.

如何捕获MysqL警告？

1)If the statement executes but there is a MysqL warning I want to capture that to last_sql_warning.txt

最简单的方法是简单地将MysqL警告提升为错误,您已经知道可以记录这些错误.这样就可以了：$DBHandle-> do(q | SET sql_mode =’traditional’|);

更难的方法是通过SHOW WARNINGS枚举警告,您可以检查MysqL_warning_count属性是否报告遇到警告.但是,在撰写本文时,DBD :: MysqL不方便地仅为语句(而不是数据库)句柄公开该属性.

更新：DBD :: MysqL自4.025(2013-11-05)在数据库句柄上支持此属性,因此下面的代码可以简化为$dbh-> {MysqL_warning_count}检查.

因此,您可能会这样做：

my $warnings;
my $ok = eval {
           my $sth = $DBHandle->prepare($MysqLCmd);
           $sth->execute();
           $warnings = $sth->{MysqL_warning_count};
           1;
         };

unless ($ok) {                   # Some error encountered
  ... # log it
} elsif ($warnings) {            # Some warning(s) encountered
  ... # open log file

  my $warnings = $DBHandle->selectall_arrayref('SHOW WARNINGS');
  for my $row (@$warnings) {
    # @$row is something like ('Warning',1265,"Data truncated for column 'col' at row 1")
    ... # log it
  }
}

如何重试因特定错误而失败的语句？

2)If the statement failes do to a lock timeout i would like to re-submit the query up to two times

在错误处理分支中,检查$DBHandle-> err以查找您关心的MysqL错误代码(可能没有.1205,ER_LOCK_WAIT_TIMEOUT),并根据需要重试.

猜你在找的Perl相关文章

漫谈 Perl 的 web 应用开发框架
忍不住在 PerlChina 邮件列表中盘点了一下 Perl 里的 Web 应用框架（巧的是 PerlBuzz 最近...
perl中bless的理解
bless有两个参数：对象的引用、类的名称。 类的名称是一个字符串，代表了类的类型信息，这...
PERL GB2312 UTF-8 编码转换
gb2312转Utf的方法： use Encode; my $str = "中文"; $str_cnsoftware = encode(&...
perl 计算硬盘利用率
  perl 计算硬盘利用率， 以%来查看硬盘资源是否存在IO消耗cpu资源情况； 部份代码参考了...
perl之变量
1 简单变量 Perl 的 Hello World 是怎么写的呢？请看下面的程序： #!/usr/bin/perl print ...
Perl 中的正则表达式
正则表达式是 Perl 语言的一大特色，也是 Perl 程序中的一点难点，不过如果大家能够很好的...
Perl和Shell区别
在学习Perl和Shell时，有很多人可能会问这样一个问题，到底先学习哪个或者学习哪个更好！ ...
Perl命令行应用介绍
Perl 有很多命令行参数. 通过它, 我们有机会写出更简单的程序. 在这篇文章里我们来了解...
perl的特殊变量
转自： http://bbs.chinaunix.net/thread-1191868-1-1.html# 让你的perl代码看起来更像per...
Perl BackConnectShell + Rootlab t00l
2009-02-02 13:07 #!/usr/bin/perl # D.O.M TEAM - 2007 # anonyph; arp; ka0x; xarnuz # ...
PHPJavaJava SEPythonC#C&C++RubyVBasp.NetGoPerlnettyDjangoDelphiJsp.NET CoreSpringFlaskSpringbootSpringMVCLuaLaravelMybatisAspGroovyThinkPHPYiiswoole
文件时间pythonm相等性PHP Warning时间问题问题解决pcntl_signal采样点wav模块动态文本调用频率限制对外暴露多个访问请求更新数据表模型结构type()方法比较速度手写体sobel算子保存模型Image类nn.Conv2dpytorch1.0kaggleDCGAN交并比range()用法打印模型反卷积卷积