Hi, Given this kind of sensors (Internet-of-Things) log and monitoring scenario: * There are 3 production machines monitored every few seconds for forthcoming (~2) years. * Machine m1 is emitting 20 boolean and 20 float4 captured in sensors (m1s1..m1s40). * Machine m2 has same attributes as m1 plus 10+10 more (m2s1..m2s20). * Machine m3: like m2 but half of the attributes are different. * Queries are happening once every day, like: SELECT m1s1,m1s2 FROM m1 WHERE logged BETWEEN '2017-11-01' AND '2017-11-30'". So this is a kind of an "Immutable DB" with where there are * rather static schema with sources which have overlapping attributes * heavy writes, * periodic reads Would you model this schema also like my proposition, which saves place but makes it little bit more complex to insert/update due to the arrays? create table m1 ( id bigint, created timestamp, b20 bit(20) default b'00000000000000000000', farr20 float8[20] ); :Stefan