Database development and training for Birmingham and the midlands
Specialists in Microsoft Access and Visual Foxpro database training and development
I am happy to hear from existing clients but I am taking no new calls.
Frequent and automatic backups
We've all got huge hard disks now with plenty of space to hold as many backups as anyone could need. The only restriction is the hassle of making the backup and the difficulty of finding a good name for each generation. A formal Source Control System would solve both problems but that might be too restrictive in a small development shop like ours. Instead, we use this routine to generate a unique folder name based on the datestamp and copy the files across to this folder.
This is the Visual FoxPro implementation, there is a similar version here in Access VBA.
*-- Getting the date as yyyymmdd is easy with
*-- the DTOS (Date To String) function in Fox
lcToday = DTOS(DATE())
*-- The time has colons between hours, minutes, and
*-- seconds. These are illegal in a file name so
*-- change them to underscores with the CHRTRAN
*-- (Character Translate) function.
lcNow = CHRTRAN(TIME(), ':', '-')
lcTimeStamp = lcToday + '_at_' + lcNow
lcDevDir = 'D:' + SU_HOME + 'Dev'
*-- The folder E:\DevBackup\....\Backup\ must exist
lcBackupDir = 'E:\DevBackup' + SU_HOME + 'Backup\' + lcTimeStamp
fso= CREATEOBJECT ('Scripting.FileSystemObject')
fso.CopyFolder (lcDevDir, lcBackupDir)
fso = null
This code takes the development folder for this project (defined as SU_HOME) and uses WSH (the Windows Scripting Host) to copy this folder to drive E: which has a folder with the same name as the development area. All the development files are copied here into a new folder with a name like Backup\20021023_at_16-53-58. It's not a pretty name but it is easily readable and it will be unique unless I manage to run two backups within the same second.
A typical use is to copy:
Note that you will get a COM error if the folder E:\Devbackup\MyDevWork\Backup\ does not exist. A bit more work with error trapping and the File System Object will solve this problem.
In my FoxPro development work, I have this routine tied to the F12 key with an ON KEY LABEL F12 ... statement. This allows me to create a complete backup at any stage of development by pressing F12.
You may think that regular backups will take too much space but today's hard disks are sized to hold hours of video and have plenty of space when a programmer's backups are plain text files. At the time of writing we have 97,652 backup files taking up 8.62 GB of an 80 GB drive that's installed in a spare drive bay. We've also got a library of weekly and monthly backups on CD. The drive is just another level of insurance.