Attribute-oriented generalization summarizes the information in a relationa
l database by repeatedly replacing specific attribute values with more gene
ral concepts according to user-defined concept hierarchies. We introduce do
main generalization graphs for controlling the generalization of a set of a
ttributes and show how they are constructed. We then present serial and par
allel versions of the Multi-Attribute Generalization algorithm for traversi
ng the generalization state space described by joining the domain generaliz
ation graphs for multiple attributes. Based upon a generate-and-test approa
ch, the algorithm generates all possible summaries consistent with the doma
in generalization graphs. Our experimental results show that significant sp
eedups are possible by partitioning path combinations from the DGGs across
multiple processors. We also rank the interestingness of the resulting summ
aries using measures based upon variance and relative entropy. Our experime
ntal results also show that these measures provide an effective basis for a
nalyzing summary data generated from relational databases. Variance appears
more useful because it tends to rank the less complex summaries (i.e., tho
se with few attributes and/or tuples) as more interesting.