Big Flat Stacks - NULLs

Paul Looney support at ahsomme.com
Wed Jun 16 15:00:34 CDT 2010


Ben,
I should have also mentioned that Rev does not like NULLs.
This is important when importing from HC - which is very forgiving of  
NULLs.
I use something like this:

replace NULL with "" in myData

or

replace NULL with empty in myData

If there are NULLs in you HC data, Rev may skip some of it while  
importing. Rev will also have trouble sorting columns of data if  
there are NULLs.
Where do the NULLs come from? I don't know for sure but we have found  
one recipe: the user has copied some information from another program  
into an HC field; we noticed this especially when people had copied  
something from MS Word into the Notes fields in some of our HC programs.
Sorry I didn't mention this earlier. We found out the hard way.
Paul Looney

On 15/06/2010, at 11:25 AM, Ben Rubinstein wrote:

> I'm converting an old HyperCard stack for a client - it's a classic  
> HC as
> a single table DB job, with a bit of interesting functionality.   
> But it's big
> - slightly over 38,000 cards, all with one background; about 30 MB  
> on disk.
>
> It's _very_ slow to do various things - but possibly that's only in  
> the IDE (clients would use the stack with StackRunner or similar).   
> But doing anything with it in the IDE is a pain.
>
> The way the stack is used historically is doing simple searches,  
> and flipping through matching cards, making simple edits.  I could  
> move all the data into a SQLite db and just make a single-card Rev  
> interface; the client's used to using HC and Rev stacks so I have a  
> slight preference to keeping it as a stand alone stack working as  
> they're used to, but could overcome that if I had to.
>
> I'm sure that there is wisdom in the community about this!  Would  
> storing the
> data as stack properties and retrieving it into and out of a single  
> card be
> faster than leaving Rev to handle it as a card data?  (The data is all
> unstyled text, btw - half a dozen or so small fields, a couple of  
> largeish
> ones.)  Or is there some magic trick to make Rev handle stacks of  
> this kind
> more efficiently?  Or is it something to do with importing from  
> HC?  Or is it an IDE issue?
>
> If I do move the data into custom properties and have a single card  
> for editing, are there known benchmarks - disk space, memory usage,  
> speed - comparing one property for each 'field', or a single  
> property with '2d' keys, or those fancy new-fangled 2d arrays?   
> That is, for example:
>    the uTitles[iOldCard] of this stack
>    the uAllData[iOldCardID,"Title"] of this stack
>    the uAllData[iOldCardID]["Title"] of this stack
>
> All wisdom gratefully received.
>
> Ben
>
>
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