Subform and query not displaying information based on input from a primary form

[Eddy Sincere]

I have a simple Form/Sub form design where the sub form displays records based on data in a text box on the primary form. I use two scroll buttons so the user can shift between records but the data in the sub form isn't changing.

Primary form = frmLbl

Sub form = SF01Clrs
Sub form query = qryLBL01N01Clrs

I know this is a simple answer, but I cannot figure out what's wrong. I've attached the DB for reference. Any help is appreciated.

[ItsMe]

...where the sub form displays records based on data in a text box on the primary form...

Have you used the Link Child Fields and Link Master Fields properties of your Subform control?
https://msdn.microsoft.com/en-us/lib.../ff195880.aspx

[Eddy Sincere]

Yup. It doesn't work.

[June7]

Actually, the Master/Child Links properties are not set. Unfortunately, setting them causes 'expression too complex error'. Odd. I rebuilt forms and the linking works.

ItmNmbr in Itm is described as "Item Number of the product, must be unique" yet it is set for Indexed Yes (Duplicates OK). This is contradictory.

Remove the dynamic parameter from the subform RecordSource query. It is useless. Subform loads before main form - I know sounds backwards but is true.

[Eddy Sincere]

Yes, I deleted the Master/Child properties because I kept getting the error message. And, I didn't really need it because I just made the field in the query equal the Master form (Forms!frmLbl!IDItm). Quick question - Is it good practice to set the Master/Child relationship? Or should I leave it blank and set the query criteria to pull based on the Master form?

Also, I did have the ItmNmbr as the primary key, but switched it because it's a short text field and not an autonumber field. Once I switched the PK the error message started and the query stopped working. The contradiction is due to me forgetting to change the text in the description.

I was really hoping that I was overlooking something simple (which is usually the case) so that I wouldn't have to rebuild the form. However, it looks like a rebuild is in order.

Thanks for taking the time to answer my question, especially on a weekend!

[June7]

Subform query referencing main form field won't work because as noted, subform loads before main form so the field from main form is not available to the subform when it loads. And the subform won't automatically requery when navigating main form records.

Master/Child Links properties are intended to synchronize main and subform related records.

I don't know what was causing the error. I couldn't see anything in the VBA procedures to cause issue. Sometimes objects get corrupted and cause can never be determined.

Create new forms and can probably copy/paste controls from the originals without propagating the error but sometimes controls can become corrupted. Code will not accompany the copied controls.

[Eddy Sincere]

Got it! Thanks for the information regarding Master/Child relationships, it's very helpful. This thread is solved.