Re: st: Deleted a ROW

[Steven Samuels <sjhsamuels@earthlink.net>]

Shehzad-

Within a Stata session, you can recover data only if you run - 
preserve- before making changes. However the best way to recover data  
is preventive.

1. Never write "save, replace".  Always save to a different permanent  
data set.  If your original data is "d01", for example, your next  
permanent save might be to d02.  If you mistakenly drop something,  
it's still there in the original data.
2. Do all your final work with "do files" that you number and save.

If you take this approach, you will never lose data; you will be able  
recreate all your analyses and data up to any previous state. If you  
have mistakenly dropped some observations, for example, you can re- 
edit the do file;  correct the -drop- statement; then rerun the do- 
file on the data it started with.

I've written down the protocol for data management and documentation  
that I follow. It is based on a 1981 article by Muller, Christiansen,  
and Smith , ("Guidelines for managing datasets, programs and  
printouts in scientific research," Computer Programs in Biomedicine  
13:281-288) and on a 1985 STATA net course, co-taught by Bill Gould,  
if I remember rightly.  The protocol is certainly not the last word  
(google "subversion version control"), but it works for me and I'd be  
happy to share it.

-Steve


On Aug 7, 2008, at 4:58 PM, Shehzad Ali wrote:


> Following on from this, I wonder if there is a drop and recover  
> option is Stata. What I mean is if you dropped observation/s or  
> variable/s, is there a way to recover them?
>
> Regards,
>
> Shehzad
>
> On Aug 7 2008, Hind Sbihi wrote:
>
>
> > Hi Daniel
> >
> > In the absence of more information, I will assume that each row  
> > has a unique identifier. Say your identifier is number_id and you  
> > want to remove the row for number_id #49. You can use the command  
> > drop drop if number_id==49
> >
> > HTH
> > Hind
> > -----Original Message-----
> >
> >
> > > Date: Thu Aug 07 10:33:41 PDT 2008
> > > From: "Daniel Sepulveda-Adams" <sepul003@umn.edu>
> > > Subject: st: Deleted a ROW
> > > To: statalist@hsphsun2.harvard.edu
> > >
> > > Hi,
> > > I have a question about "Deleted a ROW", I don't know how to do  
> > > that.
> > > Thanks you for your time
> > > Regards -- DSA
> > > *
> > > *   For searches and help try:
> > > *   http://www.stata.com/help.cgi?search
> > > *   http://www.stata.com/support/statalist/faq
> > > *   http://www.ats.ucla.edu/stat/stata/
> > *
> > *   For searches and help try:
> > *   http://www.stata.com/help.cgi?search
> > *   http://www.stata.com/support/statalist/faq
> > *   http://www.ats.ucla.edu/stat/stata/
> --
> Shehzad I Ali
> Department of Social Policy & Social Work
> University of York
> YO10 5NG
> +44 (0) 773-813-0094
>
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/