Remote table joining and where conditions
Hi guys, I've two questions on July2015 release of monetdb. 1) If I have two VMs (vm1, vm2) with monetdb installed: on vm1, there is a table named t1, and it's also accessible on vm2 via remote table alias rt1, and there's another table on vm2 named d2. If I do a table join on rt1 and d2, what happens here ? a. Is it true that data in t1 are fully loaded into vm2, and table joining happens on vm2 ? b. If I add a where condition on d2, what happens ? Is it true that data of t1 are pre-filtered by this newly added condition before sent to vm2 ? c. If there's another table on vm1 with the same name of 'd2', with where condition on d2 added, what happens then ? p.s. all queries are requested on CLI of vm2. 2) is there anything like partition key of prestodb in a partition table, such that some partitions can be fully skipped when querying with a where condition on these partition key provided ? thanks wu
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Wu XIANG