Hi, Thank you for your write, this is encouraging, using H2 in RaspberryPIs. Will MVStore support aggregate queries? From H2 Website, I read, MVStore is a default storage engine 1.4 onwards. We want to perform aggregation over sum/count,min/max, etc with Window functionalities, I could not find any example with MVStore doing the same.
For SD card, we can batch records like 5 Sec/10 Sec, that can produce optimal performance, considering Log Structured Storage architecture, there is not much overhead, as the data by default goes into append only mode, ie written at the end of the file, which is a good part. Any pointer would help us, how to use MVstore APIs to achieve aggregations.. Thanks. On Tue, Apr 23, 2019 at 12:19 AM <arief.has...@gmail.com> wrote: > > > Hi, > > If you could go lower level MVStore is your best friend mate, specially > with its blazing fast in-memory. I use it at RPi for around 5 millions log > records at around 3000 records/min (i batch write every 1 minute write). > Row size is around 60 bytes and with compression my data size is a mere > 90MB ish. But you need to go lower level, KV instead of SQL. aggregating > 10,000 rows would not be a problem as MVStore has a fast iterator. > Now i am not sure about writing 100+/sec to sd card, if i were you and > could tolerate some data loss, i would batch write it, say every 10 seconds > or so, if you must not loose any data then you still at the mercy of os > page cache and fsync mate. > My RPi has been running on sandisk sdcard 24/7 for about 2 months plus now > without corruption. > > Cheers > > -- > You received this message because you are subscribed to the Google Groups > "H2 Database" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to h2-database+unsubscr...@googlegroups.com. > To post to this group, send email to h2-database@googlegroups.com. > Visit this group at https://groups.google.com/group/h2-database. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to h2-database+unsubscr...@googlegroups.com. To post to this group, send email to h2-database@googlegroups.com. Visit this group at https://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
