I have a large dataset (about 1 million data points from a 68-dimensional state space, result of an MCMC simulation) which won't fit in memory. I think that the only solution for analyzing this is saving it in relational database (when generated) and then reading back only portions of this data. I have installed & initialized MySQL and the RMySQL package (I know nothing about SQL, unfortunately, but I will try to learn). The code from section 4.3.1 of the R Data Import/Export manual runs successfully. Questions: 1. should I use dbWriteTable(..., overwrite=FALSE, append=TRUE) for repeatedly saving the chunks of data? 2. is it OK to make row.names=FALSE when writing? 3. how do I retrieve only parts of the data? dbReadTable returns the whole thing if I understand correctly. If somebody has written code for analyzing data in parts before, I would appreciate if he could send it. Thanks, Tamas