Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

Hello, Thanks for your advice! It works pretty well when I dropped the rowid and set the other field as primary key. I also enable wal mode at the cost of a little bit read performance. Overall, it works really well now. Really appreciate your help. -- Sent from:

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

Thanks for the advice! I could never thought about this. Really learnt a lot. It's a customized Android phone type device. -- Sent from: http://sqlite.1065341.n5.nabble.com/ ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

> I've also attached results of "EXPLAIN UPDATE ITEM SET FIELD4 = 10 WHERE DS = 15;". Not zipvfs specific, but that kind of update can be quite inefficient if the record is large (in terms of bytes, or records per database page) as your table declaration hints to. This will be especially

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

On 9 Sep 2017, at 9:11pm, Teg wrote: > Is it a phone or tablet? I'd wonder if the CPU is going into thermal > throttle mode. As I understand it most phones and tablets can't keep > the CPU's running full speed without eventually throttling the CPU. I would never have

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

Hello Yue, Is it a phone or tablet? I'd wonder if the CPU is going into thermal throttle mode. As I understand it most phones and tablets can't keep the CPU's running full speed without eventually throttling the CPU. To me the fact uncompressed, while moving much more data, is more than 2

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

Thanks for the advice. I'll try them now. -- Sent from: http://sqlite.1065341.n5.nabble.com/ ___ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

Are your updates sorted by DS? If your queries are sorted then sequential queries are more likely to hit the same db pages while searching the index, resulting in higher cache usage and fewer decompression operations. This would have less benefit if your 100k DS values of the updates are

Re: [sqlite] Seeking advice on improving batch sql update performance on zipvfs

Yue Wu wrote: > Hello, > As mentioned in the subject, our goal is to improve performance regarding > to batch sql updates. > The update sql as follow, > >> UPDATE ITEM SET FIELD4 =? WHERE DS=? > > We run 100,000 updates in a single transaction. The zipvfs version takes >

[sqlite] Seeking advice on improving batch sql update performance on zipvfs

Hello, As mentioned in the subject, our goal is to improve performance regarding to batch sql updates. The update sql as follow, > UPDATE ITEM SET FIELD4 =? WHERE DS=? We run 100,000 updates in a single transaction. The zipvfs version takes about 20 min while uncompressed version takes about 7

Re: [sqlite] seeking advice

Hello, Rene > Hi there, > > I have to store and retrieve up to 2000 parameters. > The parameters can have real and integer values. > The max. change rate is 100ms and the max. duration is up to some hours. > > The simple solution would be to use plain binary files. It's fast but not >

Re: [sqlite] seeking advice

On 2014/12/09 22:41, Rene Zaumseil wrote: Hi there, I have to store and retrieve up to 2000 parameters. The parameters can have real and integer values. The max. change rate is 100ms and the max. duration is up to some hours. The simple solution would be to use plain binary files. It's fast

Re: [sqlite] seeking advice

On 9 Dec 2014, at 8:41pm, Rene Zaumseil wrote: > Version 3: One table with time stamp, parameter id and parameter value > - Is it working when all values change? > - Is retrieving values for one parameter fast? That one. Versions 1 & 2 will both, technically, work,

[sqlite] seeking advice

Hi there, I have to store and retrieve up to 2000 parameters. The parameters can have real and integer values. The max. change rate is 100ms and the max. duration is up to some hours. The simple solution would be to use plain binary files. It's fast but not flexible. So I came to sqlite.

RE: [sqlite] Seeking advice on On Demand Loading

2007 3:48 PM To: sqlite-users@sqlite.org Subject: [sqlite] Seeking advice on On Demand Loading Hello, I'm looking for some advice on implementing 'On Demand Loading' in my program. Some GUI controls such as a Listview have a 'virtual mode' where the control only needs to be loaded with the items

[sqlite] Seeking advice on On Demand Loading

Hello, I'm looking for some advice on implementing 'On Demand Loading' in my program. Some GUI controls such as a Listview have a 'virtual mode' where the control only needs to be loaded with the items currently shown. The Listview will call a callback function where it indicates which items