How to remove part of filename

oceanhai · Post by **oceanhai** » Mon Jun 04, 2007 10:58 pm

I want to do something really simple but I need someone to point me in the right direction. I'd like to remove the 4 characters after the time stamp and before the "." in a filename for all files in a given directory. Here is an example:Rename these filesdb1_db_200706051234.bakdb2_db_200706051234.bakdb3_db_200706051234.bakdb4_db_200706051234.bakTo thisdb1_db_20070605.bakdb2_db_20070605.bakdb3_db_20070605.bakdb4_db_20070605.bakShould I use a regular expression? A wildcard? Thanks for any help you can offer.Ryan

oceanhai · Post by **oceanhai** » Mon Jun 04, 2007 10:58 pm

I want to do something really simple but I need someone to point me in the right direction. I'd like to remove the 4 characters after the time stamp and before the "." in a filename for all files in a given directory. Here is an example:Rename these filesdb1_db_200706051234.bakdb2_db_200706051234.bakdb3_db_200706051234.bakdb4_db_200706051234.bakTo thisdb1_db_20070605.bakdb2_db_20070605.bakdb3_db_20070605.bakdb4_db_20070605.bakShould I use a regular expression? A wildcard? Thanks for any help you can offer.Ryan

Post by **jhicks** » Mon Jun 04, 2007 11:45 pm

One way might be to use the Left function on the filename to retrieve the first 14 characters:sOldfile=db1_db_200706051234.baksNewFile=Left(sOldFile,14) & ".bak"

oceanhai · Post by **oceanhai** » Mon Jun 04, 2007 11:54 pm

Thanks for your reply. I'd thought about that but the db name is different for every db (a different number of characters). I also thought about just deleting the 4 characters to the left of the "." in the filename but I wouldn't want to accidentally delete the characters for YYYYMMDD on filenames that had already been modified the day prior. Basically, I just want to check once daily to make sure all files in a directory have the format of dbname_db_YYYYMMDD.bak and delete the HHMM (hours and minutes from the timestamp in the filename when necessary).

Post by **jhicks** » Tue Jun 05, 2007 12:22 am

Then you'll need to use regular expressions. A pattern like this will match or verify the entire filename^([a-zA-Z0-9]*)_ww_dddddddd.bak$Of course with Regex you can slice and dice this many ways. You might use Regex to extract just the matching pattern:strString="db1_db_200706051234.bak"strPattern="^([a-zA-Z0-9]*)_ww_dddddddd"strNewFile=Trim(GetMatch(strString,strPattern))Function GetMatch(strString,strPattern) Dim RegEx,arrMatches Set RegEx = New RegExp RegEx.IgnoreCase = True RegEx.Global=True RegEx.Pattern=strPattern Set colMatches=RegEx.Execute(strString) For Each match In colMatches strResults=strResults & " " & match.value Next GetMatch=strResultsEnd Function

oceanhai · Post by **oceanhai** » Tue Jun 05, 2007 3:39 am

I've used your regular expression script and added some functionality to rename files. However, I'm getting an error stating "(21, 2) (null): The system cannot find the file specified."Here is the script I'm using. If I run the rename command manually it works fine.Dim strSourceString, strNewString, strRenameCommandSet ws = WScript.CreateObject("WScript.Shell")Set objFSO = CreateObject("Scripting.FileSystemObject")objStartFolder = "C:ScriptsDevRenameBAKFilesBackup"Set objFolder = objFSO.GetFolder(objStartFolder)Set colFiles = objFolder.FilesFor Each objFile in colFiles strSourceString = objFile.Name Wscript.Echo strSourceString strPattern="^([a-zA-Z0-9]*)_ww_dddddddd" strNewString=Trim(GetMatch(strSourceString,strPattern)) strNewString=strNewString & ".bak" strStartFolder = objStartFolder WScript.Echo(strNewString) 'Rename Files strRenameCommand = "ren" & " " & strStartFolder & "" & strSourceString & " " & strNewString WScript.Echo(strRenameCommand) ws.Run(strRenameCommand)Next'strString="db1_db_200706051234.bak"Function GetMatch(strString,strPattern) Dim RegEx,arrMatches Set RegEx = New RegExp RegEx.IgnoreCase = True RegEx.Global=True RegEx.Pattern=strPattern Set colMatches=RegEx.Execute(strString) For Each match In colMatches strResults=strResults & " " & match.value Next GetMatch=strResultsEnd Function

Post by **jhicks** » Tue Jun 05, 2007 4:29 am

Oh, you need to specify cmd.exe in the rename command strRenameCommand = "cmd /c ren" & " " & strStartFolder & "" & strSourceString & " " & strNewString

oceanhai · Post by **oceanhai** » Tue Jun 05, 2007 4:48 am

Great! Everything tests out fine now. Thanks for all of your help.

oceanhai · Post by **oceanhai** » Thu Jun 21, 2007 3:37 am

Hi jhicks,It turns out that some of the database names have one or more underscores in them, in addition to the two in "_db_" in the filename and this is causing problems with the pattern matching. For example, the match does not seem to work on a file with the name of "fred_test_data_db_200706210130.bak". Is there anything else I can add there to match an underscore "_" that could appear anywhere in the string? Thanks!

oceanhai · Post by **oceanhai** » Thu Jun 21, 2007 11:25 pm

Wait, it turns out that the pattern matching works fine on my dev machine, no matter how many underscores there are in the filename. However it is not working on the prod server. Any filenames that contain an underscore, other than the two in "_db_", will be skipped over and not renamed.The only difference I can think of is that my dev machine is Win2k3 sp1 and the prod machine is Win2k sp4. Has anyone seen anything like this? Is there an upgrade or patch that I might try? Thanks.

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