topic Re: Packed librairies Dynamic call, Database connection not transfered to Vi in LabVIEW

Packed librairies Dynamic call, Database connection not transfered to Vi

WengerR — Thu, 12 Jan 2017 13:15:57 GMT

I have an application which dynamic call vi in a packed librairies.

The VIs called have all the same connector with 10 clusters and an a DataBase connection.

The data from the cluster are well transfer to the VIs, but not de DataBase connection.

I received the error: NI_Database_API.lvlib:Conn getData.vi"<ERR>Object 0x9D00000 is not valid.

(I'm using Labview 2010)

Re : Packed librairies Dynamic call, Database connection not transfered to Vi

AllamSamir — Fri, 13 Jan 2017 08:34:11 GMT

HI WengerR,

Could you send us the VI ?

Have you ever successfully logged in to the database ?

Best regards,

Re : Packed librairies Dynamic call, Database connection not transfered to Vi

WengerR — Fri, 13 Jan 2017 09:34:47 GMT

The data base connection work fine. If a call directly de vi I have no trouble but when it's packed in a librarie the connection don't work.

My main vi is very big to be able to send you so I create I litle example vi which reproduce my trouble.

I have remove the opening of the database so you'll have to add an opening to your own database and chose a request you want to execute.

The request will be run in the main vi and then in the vi call dynamic.

Best regards

Re : Packed librairies Dynamic call, Database connection not transfered to Vi

WengerR — Mon, 30 Jan 2017 14:28:19 GMT

I think my trouble come from the fact when I packed the libraires the database connecton definition is not keep in the right way. it's probably disconnected from definition.

So My trouble is probably more a trouble with type def.

But I don't find a solution to my problem.

Re : Packed librairies Dynamic call, Database connection not transfered to Vi

Yamaeda — Mon, 30 Jan 2017 16:33:50 GMT

I might be wrong, but i think a packed library is a namespace of its own, thus the reference won't work. You'll need to keep track of the ref inside the library through some Open/Close functions.

Re : Packed librairies Dynamic call, Database connection not transfered to Vi

Ben — Mon, 30 Jan 2017 16:41:46 GMT

@Yamaeda wrote:

I might be wrong, but i think a packed library is a namespace of its own, thus the reference won't work. You'll need to keep track of the ref inside the library through some Open/Close functions.

/Y

Either that or the resource (connection) is being cleaned up when the dynamic VI is closed.

Ben

Re: Packed librairies Dynamic call, Database connection not transfered to Vi

hekdude — Fri, 03 Nov 2023 02:58:42 GMT

When I had this problem it was because I lost the reference in a for loop with zero iterations and no shift register.

Re: Packed librairies Dynamic call, Database connection not transfered to Vi

wiebe@CARYA — Fri, 03 Nov 2023 09:43:28 GMT

@hekdude wrote:

When I had this problem it was because I lost the reference in a for loop with zero iterations and no shift register.

The best way to learn not to do that is the hard way 😎.