How to disable AutoCommit on FireDac

You can do this:

FDConnection1.TxOptions.AutoCommit := False;

I think it's worth pointing out that the AutoCommit option simply clears the UpdateStatus of the records. Unlike ApplyUpdates of ClientDataSet , which returned all records to usUnModified automatically, FDQuery maintains them. I imagine it is so that we can, after giving ApplyUpdates , make new changes to the database database according to the registration status.

So, if you run ApplyUpdates in a row (for some automation, for example), you may get a primary key error among others due to the attempt to perform the same operation twice.