Category Archives: Twost

Data Type Mapping for OLEDB Providers

Posted on by

I recently had a question on the #sqlhelp hashtag on Twitter regarding how OLE DB Providers map the data columns to SQL Server data types.

The Data Type Mappings for SQL Server for distributed queries are mentioned here. The DBType values for each data that you are retrieving from a non-SQL data source like Oracle, Excel, Access can be found out using RowSet Viewer. The Microsoft® Developer Network (MSDN®) Platform SDK contains an OLE DB RowsetViewer sample application written in Microsoft Visual C++®. This application enables you to connect to either the Microsoft OLE DB Provider for AS/400 and VSAM or the Microsoft OLE DB Provider for DB2, open a table window, type the host file name or DB2 database, return a rowset, and browse the contents.

Using Rowset Viewer you can get the DBType of each column returned from the remote data source. The function used is IColumnsRowset::GetColumnsRowset. Using this you can create the necessary schema on the SQL Server database which will act as the destination for the data received from the remote data source.

Happy DB Scheming! Smile

How fetch sysaltfiles information using Powershell

Posted on by

I recently have developed an affinity for using Powershell. I saw a question on #sqlhelp hashtag for fetching database properties using Powershell. There are multiple posts out there on the web to do this using SMO. A crude way would be to use the Invoke-Sqlcmd cmdlet to do this.

Command:

Invoke-Sqlcmd -Query "SELECT filename,size,dbid FROM sys.sysaltfiles;"

If you wanted a cleaner output or some post processing done on the results fetched and wanted to use foreach, them this could also be done:

Example:

$dbprop = Invoke-Sqlcmd -Query "SELECT filename,size,dbid FROM sys.sysaltfiles;"
foreach ($db in $dbprop)
{
Write-Host $db.filename
}

If you are using SQLPS, then the above command to give the information that you want by invoking SQLCMD using Powershell.

Other ways to do this are mentioned here:

Get SQL database size using Windows Powershell

Get database properties using PowerShell in SQL Server 2008 by Tim Chapman (Blog)

How to find out BINN folder path using WMI

Posted on by

A reply to a Tweet on #sqlhelp prompted me to look this up. The question was on finding out the SQL Server BINN folder path. This can be done using WMI in the following manner for SQL Server 2008:


strComputer = "."

Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\Microsoft\SqlServer\ComputerManagement10")

Set colItems = objWMIService.ExecQuery( _

"SELECT * FROM SqlService WHERE SQLServiceType = 1 and ServiceName = 'MSSQLSERVER'",,48)

For Each objItem in colItems

Wscript.Echo "-----------------------------------"

Wscript.Echo "SqlService instance"

Wscript.Echo "-----------------------------------"

Wscript.Echo "BinaryPath: " & MID(objItem.BinaryPath,1,InStr(objItem.BinaryPath,"sqlservr.exe")-1)

Next

The SQL Server 2008/R2 WMI namespace has visibility for SQL Server 2005 also. So the above snippet of code can be used to retrieve the BINN path (PathName property contains the fully qualified path to the service binary file that implements the service) for the SQL instance. You can change the SQLServiceType to a different value to get the Binary Path folder for other services as well. The value is the above code is set to 1 for the Database Engine. The ServiceName parameter can be used to filter down the results.

For a named instance, you would need to change the service name to MSSQL$INSTA if your instance is called INSTA.

The same is possible through the much talked about Powershell as well.

Other ways to do this would be to use the xp_instance_regread XSP which is not recommended as it is an undocumented command. An example is show here.

Thanks to @afernandez for pointing out another way through a CLR TVF.