DAO vs ADO Stability (1 Viewer)

[cheuschober]

So playing along with one of my 2k databases this weekend and when I went to backup the database I had a very random error which systematically destroyed both my existing database and my new one *gah!*

Well, I inspected what I could and found the MSysObjects table missing (never a good sign) but surprisingly many things were salvageable including all my tables. In fact the only non-salvagable items were some of my forms, some of my modules, and some of my reports. Now, where thing get suspicious is in that I can recover design views of the busted forms and the reports but the embedded code modules are off-limits and what's more, of the forms, modules, and reports... the only ones that were 'unsalvageable' (directly at least) were those with DAO functions in them. All of my non-recordset functions were intact as were the modules that used ADO exclusively.

Now, initially, I was using DAO because it seemed recommended by most people here for being faster and more reliable(?) but this has given me pause. Before I go back and rebuild some of these missing items does anyone have any insight or similar problems happen? Is ADO the way to go?

Regards,
~Chad

 

[KenHigg]

I was under the impression that ADO was the future and DAO was being phased out...

This is a not an Access Link (Almost at the bottom of the page - 'Obsolete Data Access Technologies'), but was a flag for me...

 

[Pat Hartman]

That article is in direct contradiction to what I was told by the Access development team when I met with them in March. I will forward the link and suggest a modification to the article.
Microsoft is no excpetion, as with many large corporations, occassionally the left hand doesn't know what the right hand is doing. Based on the date of the article, it was written prior to the decision to put more emphasis on Access in the world of development and therefore prior to new decisions regarding Jet and DAO. Keep in mind that recordset clones are DAO even in A2003 and there are still things that DAO does that ADO does not.

 

[KenHigg]

Maybe it was just in ref. to VBA and maybe other .net stuff? At any rate, thanks for the clarification. BTW - Just what are some of the major upsides to DAO (vs ADO)?

 

[cheuschober]

Maybe it was just in ref. to VBA and maybe other .net stuff? At any rate, thanks for the clarification. BTW - Just what are some of the major upsides to DAO (vs ADO)?

Yeah, I'm with you Ken. I'm very curious to know the advantages / disadvantages of each..

 

[WindSailor]

I am glad Microsoft is sorting out things.
But I missed any updates to what is going to happen with DAO and Access in future builds. I take it they are staying with the Jet engine and leaving the status quo alone for now (sorry for being redundant, but to me this is important - because at one point Microsoft threw up their hands and said that Jet was dead, period! and I have always associated Jet with DAO - right or wrong?)?

My understanding of DAO vs. ADO is that the Jet engine fully supports DAO and not all of ADO, so there are functionality issues. Is that correct?

I see the next release (Office) incorporates XML (XML based? it has been awhile since I have seen the update) which is the basement floor for .Net.


Here is another link they need to make current.

Deprecated Components (Your going the have to click on "Deprecated Components" listed in the left hand column)

 

[Pat Hartman]

Windsailor, your link doesn't work. When posting a link to the MSDN, be sure to press the sync to toc button before copying the link otherwise the url is usually bad.

ADO is a generic data access method. It is intended to work with a variety of RDBMS including Jet. DAO was created for Jet and expanded to work with other RDBMS.

I wish I could give you details but I signed an NDA so I can't. The beta 1 for the next version of Office is being released in the middle of August. Perhaps I will be able to talk more after that.

 

[cheuschober]

So... NDA in standing --

When you just need basic recordset operations (retrieving data) or moving through a cursor or adding a record within one Access db, what do you use Pat?

~Chad

 

[Pat Hartman]

Here are three of the many articles that mention the limitations of ADO vs DAO when working with Jet.
http://msdn.microsoft.com/library/d...s/vbcon98/html/vbconadocomparedwithrdodao.asp
http://msdn.microsoft.com/library/d...singadoordaoforworkingwithaccessdatabases.asp
http://support.microsoft.com/default.aspx?scid=kb;en-us;225048#XSLTH3151121122120121120120

 

[KenHigg]

Hum... Interesting. Thanks Pat.

 

[wazz]

See the first couple of pages of chapter 6 and the first couple of pages of chapter 7 of Access 2003 VBA Programmer's Reference (Wrox). (Adds some detail to what Pat said in post #7 above.)