Here is what I would like to accomplish:
1. Construct a blank "template" drawing that already has a pre-determined data extraction table set up with every piece of valueable data that may or may not be used in the drawing showing values of zero (because there is nothing drawn yet of course)
2. The data extraction table is linked to an excel file. This excel sheet will recieve data from the linked CAD data extraction table and use the data in the pre-determined 'destination' cells to execute cost economics equations
3. I would like the data extraction table to be set up with all possible entities that may potentially get drawn into the drawing - I don't know if this is possible because in any data extraction table I have ever drawn, as soon as the entity the data table is accounting for is deleted from the drawing, the whole line from the table dissappears - in my case I would love for it to just show "zero" or null
4. The reason for all of this is to not have to create a new data extraction table and excel sheet every time - The two templates would already be linked, and all the drafter would do is draw the drawing, the appropriate data would show up in the data extraction table (eg. X amount of feet of poly line, X number of Y block), be pushed to the excel sheet in predetermined locations, cells would be linked on the sheet to execute costing equations.
I hope i have been clear enough that the project represented in the drawing does not have many possible components and that is why having them all listed in a pre-designed data extraction table would not take up much space, the benifit of having everything linked before hand is the goal.
I don't know if you've done this yet, but try and set up a data extraction definition on an empty file and see how far you get with this idea. The short answer will be; not very far. Very quickly in the process AutoCAD will ask what data you want to gather, and without linework or attributed blocks in the drawing there won't be anything to find. I suppose you could build a file with all your standard blocks already in it, but I'm not sure how complex that would get, or how useful really.
Unless I'm missing something I don't see this going very far unless all of your drawings are pretty similar.
I think the "rule" here is to use AutoCAD for what AutoCAD is good for and Excel for what Excel is good for. From what I can tell if a block isn't used in a drawing the extraction process won't record anything for it. So the zero idea probably won't work. But that doesn't mean you're finished. I can see creating an Excel spreadsheet with a link to the spreadsheet file you extract from AutoCAD where you use lookups or other functions to determine estimates even on zero/not found items. So in the end you extract data from AutoCAD to Excel and then use Excel to do the rest.
At least this would be my first line of attack.
This has been a (I see at as one) shortcoming for a very long time. I understand EXACTLY what you are trying to do as we have tried (and failed) to come up with an elegant solution to do the same. We have a workaround, but its ugly and the main reason we want to set it and forget it is because we want it dummy proof. (Ie Project Managers can use it ). Basically, for us, it would work perfect if we could open our template. copy some blocks around and then update the table and the excel file without having to re-run the data extraction. Right now, the table updates easily enough, but we have to run through the 8-10 steps to extract just to update the excel file. We currently have a ticket open in hopes of Autodesk seeing what we are asking for, but we are just waiting with fingers crossed for now...
We get around the the "zero" idea by adding a "ID ATTRIBUTE" to the blocks and filling that attribute with something like this "PARENT BLOCK-DO NOT COUNT IN DATA EXTRACTION". Then in Excel we just use a formula that says =IF(CELL,"PARENT BLOCK-DO NOT COUNT IN DATA EXTRACTION"," ",CELL) or something like that... All the other blocks get that attribute filled with data once we copy it from the parent block and start using it in the drawing.