You can append a dataset to the current dataset to add more rows of data. When one dataset is appended to another, variables are matched on their aliases. Variables that do not match between datasets are padded with missing values. Variables that are matched between the datasets must be the same type, but aside from that, the append process will attempt to adapt the variables to align. For variables with categories, categories are matched between the variables by name; for subvariables, they are matched by alias. Any categories or subvariables that do not match across the datasets will be kept: the resulting variable will have the superset of categories/subvariables. Any variable groupings (aka folders in the webapp's left sidebar) will persist after the append. The dataset you open first has the folders that will be applied after the append succeeds, not the folders in the new dataset that you are appending "onto" the original one.
It is recommended you verify that the datasets you are appending align as you expect prior to appending. If the system reaches the conclusion that it cannot append the data, the dataset will remain unchanged. If you look at the result and conclude it is not what you intended, you can easily return to the “automatic rollback savepoint” in Dataset History.
Before appending data, you may wish to consider creating a draft. This will allow you to append the data, verify the append performed as expected, and do any needed cleanup before pushing the appended dataset to your clients.
To append data, click the dataset name in the upper-left and then select the Append tab. You will see a list of datasets in the current project.
Select a dataset and click Next to append it. Appending may take a few minutes depending on the size of your datasets. Once you are finished, you will either see a success message or you will be informed that the append failed. If you are having trouble appending data, please contact us at firstname.lastname@example.org.