Purging records from a table (AREV Specific)
At 11 OCT 1999 03:56:09PM Steve wrote:
We are not revelation developers, only inexperienced users. We need someones help to allow us to access the tables and purge old data.
Please help.
Contact at Mabro Auto Transport 1-800-255-1568
Either Tammy or Steve.
At 11 OCT 1999 08:50PM Richard Hunt wrote:
Purging records is a very simple proceedure.
1) you "SELECT" the rows (records) to purge.
2) you "DELETEROW" (purge) them.
AND AND AND AND…
Almost all software seem to tie tables (files) together. What i am trying to say is that in table (file) "A", the records might relate to table (file) "B". So, if you purge from table (file) "A", you must also purge from table (file) "B".
Also… there might be more crossreferenced tables (files). Very very tricky stuff, this purging! You could very easily cause your software to start failing.
One example would be the following…
Consider that you have three tables (files).
1) "CUSTOMER" table (file).2) "INVOICE" table (file).3) "PAYMENT" table (file).Now if you purge rows (records) from the "CUSTOMER" table (file), you must first verify that there are no "INVOICE" rows (records) with that customer code.
If you purge rows (records) from the "INVOICE" table (file), you must first verify that there are no "PAYMENT" rows (records) with that invoice.
So you see… purging must be done very carefully. I am very suprised that your software doesnt have a "PURGE" module to do the purging.
Good luck!
At 12 OCT 1999 09:57AM Michael Slack wrote:
I would like to echo Richards cautions. I would also like to suggest that you do one thing before you to the SELECT in the SELECT/DELETEROW sequance. That is to make and play with a LIST statement first to create a report so you can make sure that your statement is getting what you really want. Once you have a LIST statement that gets you just what you want, you can easily replace the LIST with SELECT and remove the report producing section (display column names, JUSTLEN's, COLHEAD and so forth).
Depending on what the table is and what you want to clear out, it may be easier to create multiple SELECT statements and DELETEROW a section at a time so as not to create one large and complicated SELECT statement. You might want to consider creating a full backup of your application before starting any of this, just in case. At the very least, create a backup of the table(s) that you will be deleteing the rows out of.
If you can, go slow and carefully.
Good Luck,
Michael Slack