[Qgis-user] Editing Joined Tables

[Springfield Harrison]

Hello All:

Using version 3.10.10, I have joined two MS Excel files: Positions.csv 
and catalogue.xls using a common field called Tag. This is a tree 
inventory project.

All is well except I cannot edit either table from within QGIS. I need 
to create some new positions manually and generally update the tables 
continuously.

In the Join dialogue, I have selected Enable Editing but it has no effect.

I feel that different file types or a different procedure may facilitate 
this process but am exhausted from trying so many blind alleys.

Is there a trick to being able to edit joined tables?

Thanks very much . . . .

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Cheers, Springfield Harrison, British Columbia