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What a VMWare Thrill …

with 2 comments

I’d upgraded from VMWare Fusion 2 to 3 and taken care of most instances. A NASTY surprise awaited me when I tried to upgrade my Linux installations this morning.

You MUST to uninstall VMWare tools from your repository of Linux operating systems before upgrading your VMWare Fusion or ESX server. If you don’t, you can’t access the console because the drivers make the console look like this:

Perhaps I missed this note when, as an early adopted I opted to move straight to VMWare Fusion 3. I would have complied with these instructions to avoid this headache.

All that’s required now, is that: (a) I export 500 GBs worth of virtual machines to another machine running VMWare Fusion 2; (b) Individually start each machine and run the uninstall VMWare Tools command individually; and, (c) Shutdown and reposition all virtual machines on the original server.

As stated in the note, the command to remove it is:

/usr/bin/vmware-tools-uninstall.pl

Click on the note in the event the link fails to resolve, which would mean the note vanishes into oblivion some day in the future …

While I’ve another machine that’s not yet upgraded, this is a major inconvenience. It’s a shame that the Linux components don’t install automatically. It’s a shame that the install didn’t say something like, “Don’t do this if you’ve Linux virtual machines, unless you’ve removed their VMWare Tools installation.”

Another word to the wise, you don’t get the Linux Tools automatically when you download the product. The software prompts you to download the additional components when you attempt to launch a Linux environment. A cruel irony since by the time you see the prompt, you can’t! This is a change from the prior upgrade process.

Yes, haste makes waste but now I know. In the future, treat all VMWare upgrades like those from Microsoft test, re-test, re-authenticate in a small way before upgrading. Do you think VMWare really want to send that message to its customer base?

I got back to this tonight, and thanks to Red Hat’s Session Manager I was able to fix the Red Hat VMs. Launching it, I simply switched to the Failsafe Terminal and ran the following command, as per the note:

# /usr/bin/vmware-uninstall.pl

After that, I rebooted. Then, installed (mounted the VMWare Tools disk) from the VMWare Fusion menu. Opening a terminal as root, I then re-installed and configured VMWare Fusion. Those are done. As more time allows, I’ll update about the others.

I’m now reconfiguring the network since the VMWare Fusion 2 bridged at a 172.16.153 subdomain and VMWare Fusion 3 bridges at a 172.16.123 subdomain.

Written by maclochlainn

February 6th, 2010 at 11:49 am

My author’s copies came

with 4 comments

My co-author got his author copies about a week before me. The technical editor got his complementary book too the same day. I was wondering where mine got routed but now I’ve got mine, a few days after it was available on Amazon.

I think the new book looks good. John and I were probably a real pain during the editing process because we kept asking for more control during the proof copy to get things fixed. I think we messed up the release schedule by a couple weeks.

John and I think that the mastery questions in each chapter work well. My students who’ve seen it think it’s great because of the review sections and its smaller size. I’m re-verifying the code now, and it should be on McGraw-Hill’s website next week.

Written by maclochlainn

February 1st, 2010 at 4:06 pm

Posted in Oracle, pl/sql

Decoding 1005 on MySQL

without comments

If you’re using referential integrity on MySQL, you can easily run into this error with the InnoDB engine. It frequently seems to occur with an ALTER TABLE statement. It can mean many things but typically it means the data types don’t match between the foreign key and primary key column. Likewise, it can mean one of the column data types disagrees in a multiple-column foreign to multiple-column primary key constraint.

The error by itself isn’t very handy. This is a sample:

ERROR 1005 (HY000): Can't create table 'sampledb.#sql-4a0_2' (errno: 150)

You can discover more about the error by running the following command as the root superuser:

mysql> SHOW engine innodb STATUS;

It returns a dump of the InnoDB’s activity. You can see it by unfolding the complete log, if you’re interested in the details. The significant part of the log to solve this type of problem is:

------------------------
LATEST FOREIGN KEY ERROR
------------------------
100130 17:16:57 Error IN FOREIGN KEY constraint of TABLE sampledb/#sql-4a0_2:
FOREIGN KEY(member_type)
REFERENCES common_lookup(common_lookup_id):
Cannot find an INDEX IN the referenced TABLE WHERE the
referenced COLUMNS appear AS the first COLUMNS, OR COLUMN types
IN the TABLE AND the referenced TABLE do NOT match FOR constraint.

While this is more information, it isn’t necessarily enough to solve the problem when you’re new to MySQL. The first place you should look is whether the data types agree between the foreign key and primary key columns.

The most common variation that I’ve run into is where the primary key column uses a int unsigned data type and the foreign key column uses an int data type. It’s quite nice that the InnoDB Engine stops this cold. Naturally, you fix it by changing the foreign key data type to match the int unsigned data type.

Written by maclochlainn

January 30th, 2010 at 6:58 pm

Posted in InnoDB, MySQL, sql

iPad Thoughts …

without comments

This is probably defensive because I’ve had to answer the question about two dozen times since the iPad product announcement. The question is naturally, what do yo think about the iPad?

My perspective is biased by the fact that I’ve been using both DOS/Windows PCs and Macs since the 1980s. They each have merits but in short, unlike the media, I have a bias toward Apple products. In fact, I’m an old NeXT system administrator (software gone from the scene because as rumors have it, Steve wouldn’t think of letting the company become ONLY a software company).

I think the idea of the iPad for eBooks is awesome, the features are terrific. It clearly is a better opportunity for my digital movies but a bit awkward because of its size.

I can’t travel with an iPad by itself because it doesn’t support Microsoft Excel, Word, or Visio. That means I’d have to have my MacBook Pro and iPad. Ouch, the security folks will go nuts at the airport, and my bags are now heavier by about 2 pounds. The iPad is 1.5 pounds but the charger has weight too.

I understand all the logic for the device but there’s an underlying assumption in placing everything on the web. Some data can’t be on the web because of legal limits. This goes to my sticking point. Apple’s Office Suite isn’t as robust as Microsoft’s Office Suite. Keynote is easier to use and easily preferred over PowerPoint, but Numbers isn’t even close to Excel (here Apple fails). The problem with Pages is that many companies have templates built around Word and there’s no easy migration back and forth.

Perhaps Apple will reach out to Power Excel users and invest in Numbers to bring it into this millennium; and maybe they’ll also fix the portability between Word and Pages too. For example, one company I work with insists that I use Word 2003 because they’ve never updated their templates to Word 2007 (easy to do through VMWare Fusion). Then, all that’s needed is a rock solid replacement for Visio on Mac OS X.

I think that I might buy one to experiment with, just so I’m current with the product and new features. I’ve also got some product ideas that I’d like to explore but I don’t think this is a home-run like the iPod and iPhone without vitualization software to enable Windows. As an afterthought, maybe the announcement this summer will be “you can have it all now” when they port most features to the core OS X operating system. That would induce me to upgrade my MacBook Pro, wouldn’t it get you to do so too?

Written by maclochlainn

January 29th, 2010 at 2:24 pm

Sample PL/SQL Cursor Loops

without comments

A few of my students wanted me to post sample cursor loops, so here are examples of simple, FOR, and WHILE loops. There are a couple variations on approaches that demonstrate %TYPE and %ROWTYPE anchoring to data dictionary table definitions and local cursors.

Part of the idea behind these examples is to show the basic structure while mimicking the \G option of MySQL. The \G (Go) displays results as a list of column names and values by row. Ever since I discovered that in MySQL, I’ve hoped Oracle would incorporate something similar in their product. While discussing my wish list, I’d also like Oracle to make the FROM dual optional (like MySQL does) when selecting a string or numeric literal.

You can click any of the titles to view the code, which isn’t needed when you don’t have JavaScript enabled or the RSS expands them for you.

I’m sure this will help my students and hope it helps somebody else.

Written by maclochlainn

January 21st, 2010 at 10:53 pm

Posted in OPAL, Oracle, Oracle XE, pl/sql, sql

Haste makes waste, again …

without comments

I was working on a code example for my database class, got in a hurry, and changed a table name without dropping the original table. Oops!

Naturally, I got this error message.

  LOB (administrator_photo) STORE AS admin_photo
                                     *
ERROR at line 5:
ORA-00955: name IS already used BY an existing object

The LOB segment name existed but why and where. It was in the table that I forgot to drop. This query find the latent table and column while illustrating the relationship (for my students and others) between an OBJECT_NAME and SEGMENT_NAME:

SELECT table_name, column_name
FROM   user_lobs
WHERE  segment_name = (SELECT object_name
                       FROM   user_objects
                       WHERE  object_name = UPPER('&object_name')
                       AND    object_type = 'LOB');

Now, I can grab it later because it’ll happen again. ;-)

Written by maclochlainn

January 5th, 2010 at 10:31 pm

Posted in Oracle, sql

The ereg() function is gone

with one comment

Alas, poor ereg() I abused you well. PHP 5.3 has deprecated ereg() and now we must move forward with preg_match(). Along with that change, somebody asked me to show how to upload images to the file system as opposed to the database. Personally, I think they should be stored in the database.

With my bias toward databases, I threw in a virtual directory mapping in a MySQL database because it doesn’t natively support an Oracle equivalent BFILE data type. You can see this older post how to use the DBA_DIRECTORIES view in Oracle to mimic this behavior.

Naturally, MySQL is the preferred database of the person asking the question. You could also implement this exactly the same in Oracle but you really don’t want to do so. Using Oracle’s virtual directories has it’s own pre-built set of security features. They provide a more robust solution.

The code is presented as follows (setup for MySQL instructions):

  1. Create and seed the DIRECTORY table in MySQL:
-- Create a directory table.
CREATE TABLE directory
( directory_id   int PRIMARY KEY AUTO_INCREMENT
, virtual_name   varchar(30)
, directory_name varchar(60));
 
-- Seed the table with a virtual directory mapping.
INSERT INTO directory VALUES ( NULL,'CMS_IMAGES','C:\\Data' );
  1. Create a MySQLCredentials.inc credentails file for inclusion in the PHP program:
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<?php
  // Connection variables.
  define('HOSTNAME',"localhost");
  define('USERNAME',"student");
  define('PASSWORD',"student");
  define('DATABASE',"sampledb");
?>
  1. Create the PHP uploading program, named MySQLFileUpload.php:
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<?php
  // Set database credentials.
  include_once("MySQLCredentials.inc");
 
  // Declare input variables.
  $id = (isset($_POST['id'])) ? $_POST['id'] : 1021;
 
  // Upload a file to server in a mapped physical drive location.
  if (process_uploaded_file(map_virtual_directory($id)))
    print "Successfully Uploaded the file.<br />";
 
  // Map a virtual directory to a physical directory.
  function map_virtual_directory($virtual) {
 
    // Return successful attempt to connect to the database.
    if (!$c = @mysqli_connect(HOSTNAME,USERNAME,PASSWORD,DATABASE)) {
 
      // Print user message.
      print "Sorry! The connection to the database failed. Please try again later.";
 
      // Return error message.
      print mysqli_error();
 
      // Kill the resource.
      die();
    }
    else {
 
      // Initialize a statement in the scope of the connection.
      $stmt = mysqli_stmt_init($c);
 
      // Declare a case insensitive dynamic SQL statement.
      $sql = "SELECT directory_name FROM directory WHERE virtual_name = UCASE(?)";
 
      // Prepare the statement.
      if (mysqli_stmt_prepare($stmt,$sql)) {
 
        // Bind the input parameter to the prepared statement.
        mysqli_stmt_bind_param($stmt,'s',$virtual);
 
        // Execute the prepared statement.
        if (mysqli_stmt_execute($stmt)) {
 
          // Bind the result to a local variable.
          mysqli_stmt_bind_result($stmt,$directory);
 
          // FetchPrepare statement and link it to a connection.
          while (mysqli_stmt_fetch($stmt))
            return $directory;
        }
        else
          // Return error message.
          print mysqli_error();
      }
      else
        // Return error message.
        print mysqli_error();
 
          // Disconnect from database.
      mysqli_close($c);
    }
  }
 
  // Manage file upload.
  function process_uploaded_file($directory) {
 
    /* Assume the application may allow a virtual directory with a trailing backslash or forward
       slash to be stored in the database, and manage both scenarios across Windows and Linux. */
    if (preg_match(".Win32.",$_SERVER["SERVER_SOFTWARE"]))
      if (preg_match("/\b\\\/",$directory));
      else if (preg_match("/\b\//",$directory)) {
        $directory = substr($directory,0,strlen($directory)-1);
        $directory = $directory."\\";
      }
      else $directory = $directory."\\";
    else
      if (preg_match("/\b\//",$directory))
        $directory = substr($directory,0,strlen($directory)-1);
      else
        $directory = $directory."/";  
 
    // Check for, move uploaded file, and confirm processing.
    if (is_uploaded_file($_FILES['userfile']['tmp_name'])) {
 
      // Move temporary cache into a file directory with the uploaded file name.
      move_uploaded_file($_FILES['userfile']['tmp_name'],$directory.$_FILES['userfile']['name']);
 
      // Remove this from real code, it's here for example only. ;-)
      print "Uploaded [".$_FILES['userfile']['name']."] to".$directory."<br />";
 
      // Return true to encapsulate the functional logic on success.
	    return true;
    }
    else
      // Return false to encapsulate the functional logic on failure.
	    return false;
  }
?>
  1. Create a web page to test it:
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<html>
<head>
<title>
  UploadFileFormMySQL.htm
</title>
</head>
<body>
<form id="uploadForm"
      action="MySQLFileUpload.php"
      enctype="multipart/form-data"
      method="post">
  <table border=0 cellpadding=0 cellspacing=0>
    <tr>
      <td width=125>Item Number</td>
      <td>
        <input id="id" name="id" type="text">
      </td>
    </tr>
    <tr>
      <td width=125>Select File</td>
      <td>
        <input id="uploadfilename" name="userfile" type="file">
      </td>
    </tr>
    <tr>
      <td width=125>Click Button to</td>
      <td><input type="submit" value="Upload File"></td>
    </tr>
  </table>
</form>
</body>
</html>

Hope this helps a few folks. I imagine that the prepared statement with bound variables may help a few folks because it’s not found (at writing) on the php.net web site.

Written by maclochlainn

December 29th, 2009 at 2:03 am

Posted in LAMP, Linux, MAMP, PHP, Zend

CrossOver Plus Limits

without comments

While reconfiguring my iMac, it was interesting to note the bumpy road to implementing Code Weaver’s CrossOver Plus 8.0.1 for the whole Microsoft Office Suite. Previously, it had only been used to support Microsoft Visio 2007.

I discovered that a Shutdown and Start operation was required after installing CrossOver Plus because a Restart hadn’t worked. Attempting to create the WINE bottle with a reboot gave me the following error:

The Microsoft Office 2007 package requires CrossOver HTML engine to install and
run properly. Continuing with the install may produce unpredictable results.

I also found that patching the Office product failed. It’s possible that could be the network here, but there’s also no manual way to download *.msi files and apply them against the WINE bottle. It’s possible that a trick was missed and there is a way to do it. Downloading and right clicking on the *.msi file on the Mac OS X side allows you to look for an application to help but I couldn’t find a helper application in the CrossOver Plus folder tree. It may be there, however, where it is eluded me in the time my patience would allow (please comment if you know its location)?

Rather than use Google Quick Search Box I thought symbolic links would be helpful in the Applications folder since I actually also run Microsoft Office 2008. Turning to Chapter 6 in the product documentation didn’t solve the problem. It led me to an incorrect folder location.

They’re not here, as stated in the product documentation:

You can find them in the WINE bottle folders here, the default is for Windows XP:

Within the Bottle folder, you can find the Microsoft Office 2007 links here:

General Complaint

The CrossOver Plus installation suppresses the options dialog to choose a typical, full, or custom installation of Microsoft Office 2007. That means you get typical, which means you can’t connect to a remote database using the JDBC et cetera. This doesn’t meet my needs and means I’ll have to put another VMWare instance together to work with Microsoft Excel 2007 reasonably. Drat!

Written by maclochlainn

December 23rd, 2009 at 1:03 pm

The class, they survived …

with 3 comments

The rumor is that my database is hard, but I’ve always hoped it was fun and laid the foundation of success for my students. As I walked into class to give them their final exam, they had their jackets on, which isn’t uncommon for Rexburg, Idaho in December. However, that’s normal outside but unusual in the heated classroom. Then, they all took their jackets off to show their new t-shirts.

They thought it would be fun to post on the blog, so here it is. The shirts says:

SELECT   i.survived
FROM     michael_mclaughlin i
WHERE    class= CIT 320;

It’s unfortunate that they missed the enclosing quote marks around the string literal. ;-) It should be like this:

SELECT   i.survived
FROM     michael_mclaughlin i
WHERE    i.class= 'CIT 320';

Here’s to a great group of students who know how to read, write, and think SQL. Any openings out there for internships, please drop me a note.

Happy holidays!

Written by maclochlainn

December 16th, 2009 at 4:42 pm

VMWare nabs me again …

without comments

When I run into failures on VMWare Fusion, they’re always a bit tedious. This one happened on my iMac (OS X Leopard) running VMWare 2 (both constrained to old releases by university governance policies). The VM is Microsoft Vista in an IDE partition, it hung after running too long. I had to force quit the application. On reboot the socket file was still there, and it gave the following error message when trying to start it.

VMwarefusionvirtualdevice0

Here’s the error in plain text, so search engines can find it for others.

Virtual device serial0: File "/var/folders/Sf/SfvoJITAHMq1Vp8bNI7QZU+++TM/-Tmp-//vmware-mmclaugh/thnuclnt-641/socket" exists, but no server is listening to it.
 
There are three possible causes for this:
 - The server is alive but not ready yet, and you can retry later.
 - The server is busy communicating with another client, so you cannot run this client at the same time.
 - A previous server exited abruptly, and you can remove the file and try again.
 
The device will be disconnected.

How to fix it?

Delete the file, right? Yes, but there’s a trick. Navigating through the -Tmp- directory required a Unix shell trick because the - (dash) is a switch and backquoting it with a \ (backslash) didn’t work. Jeff Yoder, told me the trick to change directory into a dash leading directory name. It was this:

cd -- -Tmp-

The -- is how most shells mark the end of options to a command. After a -- all - (dashes) are treated as ordinary characters.

Mark Olaveson reminded me that using the present working directory before the directory name also worked. It demotes the dash to an ordinary character too.

cd ./-Tmp-

When I got to the directory, there was the socket file. I deleted it and everything worked like a charm.

srwxrwxrwx  1 mmclaugh  staff     0 Dec  8 13:04 socket

Written by maclochlainn

December 8th, 2009 at 3:43 pm

Posted in Linux, Mac OS X, VMWare, bash