Write to Datastore entity is not writing value to table

That node only returns if the database returns a success. Can you make sure that the instances which did work had the primary key set to null?

Adding to Stefan,

There are possibilities:

Database connection issues: One possibility is that there is an issue with the database connection. The node may not be able to establish a connection to the database or the connection may have been lost or timed out. The node may be taking too long to execute or write data.

If the node completed successfully the first time,
1. check the stdout log for info on the action

2. make sure you are capturing outputs on the node to see if success without error and value was returned (like the new PK if increment)

3. check the pv history, did the pv have a value before that write to ds was executed

I would start there...

Not sure if you're still having this issue, but I had a very similar issue which turned out to be a race condition with another process model that was writing to the same table.

You have to check database configuration like fileds are properly mapped or not