PowerShell, Scripts and Cmd.exe

PowerShell's designers don't seem to be overly concerned about including intuitiveness as a feature.  Consider what it takes to run a PowerShell script from the cmd.exe prompt. Bet

c:\> Powershell blah blah

doesn't do what you would think it would do. PowerShell expects "blah blah" to be code written in Powershell.  the canonical example is the following:

c:\> Powershell 2+2
4

Get it?  Do you ever find yourself typing "Powershell blah blah" at the command line? I didn't think so.  PowerShell is a scripting language, so you might be expecting

c:\> Powershell script.ps1

to run a script named script.ps1. Well if so, you would be wrong. PowerShell instead expects "script.ps1" to be a PowerShell command, which it obviously isn't.  The solution, for some unexplained reason, is to add an ampersand in quotation marks. Thus,

c:\> Powershell "&" script.ps1

BTW, it's more conventional to put the script reference in quotation marks as well. In other words,

> Powershell "& script.ps1"

According to the error message you receive if you type

c:\> Powershell "& blah blah"

the quoted ampersand tells PowerShell that what comes afterward is one of four things:

• cmdlet
• function
• script file
• operable program

Apparently, this error message is the only official instruction from Microsoft regarding the ampersand switch.

Changing .NET App Properties/Settings at Runtime

Visual Studio* provides an application settings (aka properties) feature for console, library or windows applications. Creating and editing application settings at design time is straight-forward and can be managed conveniently thru VS's GUI.

But what if you need to change the settings at run-time? The answer is anything but obvious. The settings are contained in a class called "Settings," which derives from System.Configuration.ApplicationSettingsBase.  You could of course rewrite the code in the settings class, but then if you decide to make a change in VS's GUI all of your handiwork is immediately hosed.

There's one adjustment you can make directly in the GUI that puts you a step closer to your goal.  At the top of the Settings Designer screen, is a drop down box titled "Accessor Modifier."  There are two choices: the default is "Internal." The other choice is "Public." Choose "Public." As we'll see, this one alteration allows us to change the value of the properties in our code.

The application expects there to be a static property called Default, of type Settings, in the class Settings. Default, the only instance of Settings that will be acknowledged by the app, is created for you automatically by VS.  Default is essentially functioning as a singleton. Finally, ApplicationSettingsBase provides an indexer allowing us to reference the individual settings on Default.

Here's an example:

MyApp.Properties.Settings.Default["MyProperty"] = value;

ORA-12154 TNS:could not resolve the connect identifier specified

Hey Oracle enthusiasts. Here's a fun one. I encounter this just about whenever I try to configure, unsuccessfully, TNSNames.ora for ODP.NET. Recently, I decided stopped worrying about TNS and put everything into the connection string, like so:

Data Source=(DESCRIPTION= (ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=LOCALHOST)(PORT=1521))) (CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME = orcl))); USER ID=whatever;PASSWORD=********;"

This works every time.

It just seems as though TNS isn't worth the trouble.

Backing Up Oracle, Easily

As a developer I have a need to replicate environments. As I now work regularly with Oracle, my environment-maintenance duties should include duplicating Oracle databases across various machines. But how in the world do you do that?

It's been a real eye-opener to research what's involved with Oracle administration. I've come to the conclusion that the Oracle company doesn't really bother itself with things like quickstarts. Sadly, all their documentation is written in documentation-ese. What a struggle.

A few days ago I broke down and tackled the Oracle restoration challenge. I finally restored my first Oracle database today, and I thought I'd document how to do it, for the benefit of others. Essentially, I copied files over from the old server to the new one. FYI, this is what as known as a "cold" backup and recovery because the databases are shutdown when the activity occurs.

1. First, run these commands in sqlplus or Sql Developer to find out which files need to be copied:
          select name from v$datafile; -- this provides the datafiles
          select name from v$controlfile; --this provides the control files
2. Note the redo files. They are in the same directory as the datafiles.
3. Now log into the database to be replicated as sysdba
          $>sqlplus "/ as sysdba"
4. And issue the "shutdown abort" command
5. Similarly on the new server, issue the "shutdown abort" command
5. Copy all the files referred to in items 1, 2, and 3 above from the server to be replicated to the corresponding locations on the new server
6. Back in sqlplus on the server to be replicated, issue the "restart" command
7. Do the same for the new server

Congratulations! You should be up and running on the new server by now.

Google, My Friend

It's astonishing to me how well Google distinguishes itself in anticipating its customers' needs. I couldn't remember the file name for the Task Manager program. I only knew that it was some abbreviation of TaskManager.

I tried doing a search on "task manager command line" or something like that receiving nothing but frustration. But then remembering Google's "Did you mean . . .?" feature. I typed "cmd tskmngr" into Google's search box. There it was.

Did you mean: cmd taskmgr

Simple. Effortless.

How Again Do You Get Data Out of a Refcursor in Sql Developer?

There appears to be no way for me to memorize how to run a stored procedure in Sql Developer that uses a refcursor. So I'm putting an example here. That way I can refer to it any time I want.


variable CV_1 REFCURSOR;
declare V_INTUSERID number;
BEGIN
V_INTUSERID := 1;
spProc1(V_INTUSERID,:CV_1);
END;
PRINT CV_1;

Visual Studio Shortcut for Using Directives

My current vote for top Visual Studio shortcut goes to "Shift-Alt-F10."  This little beauty will bring up the "Options to help bind the selected item" dialog which will allow you to command the UI to inject the appropriate "Using" directive at the top of a class. Trying to bring up this dialog with the mouse is tricky and time-consuming. Save those precious brain cells for something else.