Max Length of a column in a DataTable in PowerShell

Whilst I was writing my Test-DbaLastBackup Posts I ran into a common error I get when importing datatables into a database

I was using this table

01 - table

and when I tried to add the results of the Test-DbaLastBackup I got this

02 -error.PNG

Exception calling “WriteToServer” with “1” argument(s): “The given value of type String from the data source cannot be converted to type nvarchar of the
specified target column.”
At line:356 char:4
+             $bulkCopy.WriteToServer($InputObject)
+             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : InvalidOperationException

Hmm, it says that it can’t convert a string to a nvarchar, that doesn’t sound right.To find out what was happening I used a little bit of code that I use every single day

All errors from your current session are stored in the $error array so [0] accesses the most recent one and fl is an alias for Format-List and the force switch expands the object. This is what I saw

03 expanded error.PNG

System.Management.Automation.MethodInvocationException: Exception calling “WriteToServer” with “1” argument(s): “The given value of
type String from the data source cannot be converted to type nvarchar of the specified target column.” —>
System.InvalidOperationException: The given value of type String from the data source cannot be converted to type nvarchar of the
specified target column. —> System.InvalidOperationException: String or binary data would be truncated.

String or binary data would be truncated. OK that makes sense, one of my columns has larger data than the destination column but which one? Lets take a look at some of the data

SourceServer  : SQL2016N3
TestServer    : SQL2016N1
Database      : RidetheLightning
FileExists    : Skipped
RestoreResult : Restore not located on shared location
DbccResult    : Skipped
SizeMB        : 4.08
BackupTaken   : 3/19/2017 12:00:03 AM
BackupFiles   : C:\MSSQL\Backup\SQL2016N3\RidetheLightning\FULL\SQL2016N3_RidetheLightning_FULL_20170319_000003.bak

SourceServer  : SQL2016N3
TestServer    : SQL2016N1
Database      : TheCallofKtulu
FileExists    : Skipped
RestoreResult : Restore not located on shared location
DbccResult    : Skipped
SizeMB        : 4.08
BackupTaken   : 3/19/2017 12:00:04 AM
BackupFiles   : C:\MSSQL\Backup\SQL2016N3\TheCallofKtulu\FULL\SQL2016N3_TheCallofKtulu_FULL_20170319_000004.bak

SourceServer  : SQL2016N3
TestServer    : SQL2016N1
Database      : TrappedUnderIce
FileExists    : Skipped
RestoreResult : Restore not located on shared location
DbccResult    : Skipped
SizeMB        : 4.08
BackupTaken   : 3/19/2017 12:00:04 AM
BackupFiles   : C:\MSSQL\Backup\SQL2016N3\TrappedUnderIce\FULL\SQL2016N3_TrappedUnderIce_FULL_20170319_000004.bak

Hmm, its not going to be easy to work out which bit of data is too big here.

All I need to know is the maximum length of the columns in the datatable though so I have a little snippet that will do that for me

and the output looks like this

04 - max length.PNG

So we can quickly see that the backupfiles property is too big and change the table accordingly and no more error.

Its pretty quick too, scanning 105 rows in 56 milliseconds in this example
05 - how long.PNG

I keep this little snippet in my snippets list for PowerShell ISE which you can find here

Here is the code to add this as a snippet to ISE
and if you want to add it to your VSCode snippets then you need to edit the PowerShell.json file which is located in your user home AppData folder ‘C:\Users\User\AppData\Roaming\Code\User\snippets\powershell.json’ or by clicking File –> Preferences –> User Snippets and typing PowerShell
04 user snippets.gif

Then you can add this bit of json inside the curly braces


 

and you have your snippet ready for use

07 - snippet in vscode.gif

Happy Automating

 

 

VS Code PowerShell Snippets

Just a quick post, as much as a reminder for me as anything, but also useful to those that attended my sessions last week where I talked about snippets in PowerShell ISE

Jeff Hicks wrote a post explaining how to create snippets in VS Code for PowerShell

I love using snippets so I went and converted my snippets list for ISE (available on GitHub) into the json required for VS Code (available on GitHub)

Here is an example of snippet

[code]"SMO-Server": {
        "prefix": "SMO-Server",
        "body": [
            "$$srv = New-Object Microsoft.SqlServer.Management.Smo.Server $$Server"
        ],
        "description": "Creates a SQL Server SMO Object"
    },

I followed this process in this order

Click File –> Preferences –> User Snippets and type PowerShell or edit $env:\appdata\code\user\snippets\powershell.json

In order I converted the code in the existing snippets “Text” like this

        Replace `$ with $$
        Replace \ with \\
        Replace ” with \”
        \r for new line
        \t for tab
        Each line in “”
        , at the end of each line in the body   except the last one
        Look out for red or green squiggles 🙂
I then add
The name of the snippet, first before the : in “”
The prefix is what you type to get the snippet
The body is the code following the above Find and Replaces
The description is the description!!
and save and I have snippets in VS Code 🙂
snippets.gif
That should help you to convert existing ISE snippets into VS Code PowerShell snippets and save you time and keystrokes 🙂

PowerShell Snippets A Great Learning Tool

When I talk to people about Powershell they often ask how can they easily learn the syntax. Here’s a good tip

Open PowerShell ISE and press CTRL + J

image

You will find a number of snippets that will enable you to write your scripts easily.  Johnathan Medd PowerShell MVP has written a good post about snippets on the Hey, Scripting Guy! blog so I will not repeat that but suggest that you go and read that post. It will show you how quickly and easily you will be able to write more complex Powershell scripts as you do not have to learn the syntax but can use the snippets to insert all the code samples you require.

Not only are there default snippets for you to use but you can create your own snippets. However there isn’t a snippet for creating a new snippet so here is the code to do that

I frequently use the SQL Server SMO Object in my code so I created this snippet

I also use Data Tables a lot so I created a snippet for that too

Denniver Reining has created a Snippet Manager which you can use to further expand your snippets usage and it is free as well.

If you have further examples of useful snippets please feel free to post them in the comments below

Edit 16/12/2014

I am proud that this article was nominated for the Tribal Awards. Please go and vote for your winners in all the categories

http://www.sqlservercentral.com/articles/Awards/119953/

Personally in the article category I will be voting for

Gail Shaw’s SQL Server Howlers