When you explore/visualize a dataset, it is on a sampling. By default, the first 30,000 records of your dataset are selected for the sample. You can change that. More about sampling in the doc and in the 101 tutorial.
Since DSS 2.3, the Free Edition (or Community Edition) is no longer limited by the number of rows (100,000 rows before).
So all that does not really explain your 10,000 rows limit. How what type of connection your dataset is on?