Resolving the “ORA-12514: No TNS Listener” error with Oracle XE

I faced this particularly nagging error with a personal install of Oracle XE (Oracle Database 10g Express Edition) on my Windows XP laptop:

ORA-12514:No TNS Listener

The SQL Command prompt that came with Oracle XE would work but none of the other tools like Toad, SQL Plus or even the Oracle XE Database Homepage which would open in a browser window would work.

The final resolution after a lot of research seemed to be painfully simple:

  1. Run the LSNRCTL.EXE program from the BIN directory of your Oracle XE install (default: C:\oraclexe\app\oracle\product\10.2.0\server\BIN). You should even be able to run it from any command prompt since the BIN directory is generally added to your PATH environment variable by default.
  2. At the LSNRCTL> command prompt, issue the STOP command. It should say:

    Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC_FOR_XE)))
    The command completed successfully

  3. Now, at the LSNRCTL> prompt, issue the START command. It should return:

    Starting tnslsnr: please wait…

    TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 – Production
    System parameter file is C:\oraclexe\app\oracle\product\10.2.0\server\NETWORK\AD
    MIN\listener.ora
    Log messages written to C:\oraclexe\app\oracle\product\10.2.0\server\network\log
    \listener.log
    Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\EXTPROC_FOR
    _XEipc)))
    Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=port)))

    Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC_FOR_XE)))
    STATUS of the LISTENER
    ————————
    Alias                     LISTENER
    Version                   TNSLSNR for 32-bit Windows: Version 10.2.0.1.0 – Produ
    ction
    Start Date                14-MAY-2009 01:24:49
    Uptime                    0 days 0 hr. 0 min. 5 sec
    Trace Level               off
    Security                  ON: Local OS Authentication
    SNMP                      OFF
    Default Service           XE
    Listener Parameter File   C:\oraclexe\app\oracle\product\10.2.0\server\NETWORK\ADMIN\listener.ora
    Listener Log File         C:\oraclexe\app\oracle\product\10.2.0\server\network\log\listener.log
    Listening Endpoints Summary…
    (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\EXTPROC_FOR_XEipc)))
    (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=hostname)(PORT=port)))
    Services Summary…
    Service “CLRExtProc” has 1 instance(s).
    Instance “CLRExtProc”, status UNKNOWN, has 1 handler(s) for this service…
    Service “PLSExtProc” has 1 instance(s).
    Instance “PLSExtProc”, status UNKNOWN, has 1 handler(s) for this service…
    The command completed successfully

That’s it! That should resolve the problem. Verify by running “tnsping XE” or “tnsping dbname” at the command prompt. It should return OK.

All your tools like Toad, SQL Plus or Oracle SQL Developer should be able to connect to the database now!

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Fixing the double-letterboxing effect in Windows Media Player…

To resolve the double-letterboxing effect when playing a widescreen (16:9) movie encoded as fullscreen (4:3) on a widescreen laptop: use Videolan.

Videolan is a freeware, open-source media-player that can help to resolve this problem by providing zoom and crop features that are easily accessible with a right-click while playing the video. If you have an older version, check out the newly released 0.9.* (Grishenko) release – it’s really cool!

Upgrade issues with Norton Antivirus

Here’s what to do if you’re trying to upgrade to Norton Antivirus 2008 and getting the dreaded error message: “Setup has detected that LiveUpdate or AutoLiveUpdate is running. Setup will now abort.”:

  • There is no easy way to kill the LiveUpdate processes or services once started. The only way around this is to prevent them from starting in the first place.
  • Go to Start > Run, type services.msc to bring up the Windows Services.
  • Find all the services that start with “LiveUpdate…”, “AutoLiveUpdate…” or “Symantec…” and right-click on each one of them and go to “Properties”.
  • Set the “Startup Type” to Disabled.
  • Restart your computer and the upgrade should go smoothly this time.

If you find a better way to do this, be sure to post it here for everyone’s benefit!

Google launches new Shakespeare site

ShakespeareGoogle has launched Google Shakespeare – a site that allows readers to browse / read all 37 of the Bard's plays. Readers can even plug in words, such as "to be or not to be" from Hamlet, and immediately be taken to that part of the play.

Google Book Search, the Google product which houses the Shakespeare site, allows users to view books or parts of books through their Web browsers if the copyright has expired or a publisher has given permission to do so.

Google’s latest tool syncs your browser settings and favorites

The newest addition to Google LabsGoogle Browser Sync – allows you to sync your browser favorites, cookies, passwords and more between different machines. This is one tool I personally have been looking forward to for a long time…

Unfortunately for IE users, GBS currently works only on Firefox. It offers various options to restrict the data you want to share and can also encrypt it if needed. Go check it out and while you're there, check out the other cool stuff they have for Mozilla Firefox users!

Google Spreadsheets: taking aim at MS Office

After offering an online alternative to Word by acquiring the online word processor Writely, Google has now launched Google Spreadsheets as an online rival to Excel. NYTimes reports:

  • It would make it possible for as many as 10 people to simultaneously edit a spreadsheet document online and chat about it using Google’s instant messaging program.
  • The new service will be able to handle several hundred formulas used to manipulate data in Excel, but not more complex functions like macros.
  • The ability for many people to collaborate was quite different from the standard method of e-mailing files back and forth.

It allows uploads of existing Excel or Comma-separated values (CSV) files and your work can be exported into Excel, CSV or HTML formats. The service currently lacks charts functionality but one can imagine a creative mind at Google linking up the Spreadsheets with Google Gapminder (covered in an earlier post) to create professional charts.

These tools can really open up the vistas for online collaborative working especially between people in different locations / countries. Also, the startup costs and installation efforts are minimal (zero!) enabling mass adoption in developing economies.

Online page design tips

Eyetrack has some interesting research findings and tips on Article-Level Page Design:

  • When readers encountered a story with an introductory paragraph, 95 percent of them read all or part of the introductory paragraph.
  • Those who spent time carefully reading the introductory paragraph of a story on article-level pages typically spent little time with the full story. Those who gave the intro paragraphs little time usually spent even less time with the story text.
  • Shorter paragraphs encouraged testers to continue reading.
  • Story text in one-column format was read more extensively than story text presented in a “newspaper-like” multiple-column format.
  • Subheads in online stories had little affect on how much of the first or top portion of the story was read when the reader’s interest was strongest. However, subheads increased reading for “skimmers” and for those whose attention in a story was beginning to wane.
  • When readers got to an article-level page, they seemed to be there to view the text. Overall, participants’ eyes fixated on the story or other text elements before the accompanying image.

They also have detailed results on everything from eye-viewing patterns to headlines and font size. Useful resource!