Testing that now. Initial results are not looking too performant. I have one single table which had 234575 updates done to it. I am rolling back 13093 of them. It's been running 20 min now, using 100% of a single core, and almost 0 disk. No idea how long it'll run at this point.
This is on an i5 desktop with 16 gigs of ram and an ssd. This is a pretty good test though, as it's a real world use case (even if the data was generated with PGBench). We now know that area needs some work before it can be used for anything more than a toy database. Thanks, -Adam On Thu, Oct 2, 2014 at 7:52 AM, Felix Kunde <felix-ku...@gmx.de> wrote: > Hey there > > Thanks again for the fix. I was able to merge it into my repo. > Also thanks for benchmarking audit. Very interesting results. > I wonder how the recreation of former database states scales when > processing many deltas. > Haven’t done a lot of testing in that direction. > > I will transfer the code soon to a more public repo on GitHub. As far as I > see I have to create an organization for that. > > Cheers > Felix > > *Gesendet:* Mittwoch, 01. Oktober 2014 um 17:09 Uhr > > *Von:* "Adam Brusselback" <adambrusselb...@gmail.com> > *An:* "Felix Kunde" <felix-ku...@gmx.de> > *Cc:* "pgsql-general@postgresql.org" <pgsql-general@postgresql.org> > *Betreff:* Re: [GENERAL] table versioning approach (not auditing) > I know we're kinda hijacking this thread, so sorry for that. If you'd > like to do that, i'd be more than happy to use it and push any fixes / > changes upstream. I don't have much of a preference on the name either, as > long as it's something that makes sense. > > I would consider myself far from an expert though! Either way, more people > using a single solution is a good thing. > > As a side note, I did some benchmarking this morning and wanted to share > the results: > pgbench -i -s 140 -U postgres pgbench > > pgbench -c 4 -j 4 -T 600 -U postgres pgbench > no auditing tps: 2854 > NOTE: Accounts are audited > auditing tps: 1278 > > pgbench -c 2 -j 2 -N -T 300 -U postgres pgbench > no auditing tps: 2504 > NOTE: Accounts are audited > auditing tps: 822 > > pgbench -c 2 -j 2 -T 300 -U postgres pgbench > no auditing tps: 1836 > NOTE: branches and tellers are audited, accounts are not > auditing tps: 505 > > I'd love to see if there are some easy wins to boost the performance. > > On Wed, Oct 1, 2014 at 5:19 AM, Felix Kunde <felix-ku...@gmx.de> wrote: >> >> Hey there. Thank you very much for that fix! Thats why I'd like to have a >> joint development and joint testing. It's way more convincing for users to >> go for a solution that is tested by some experts than just by a random >> developer :) >> >> I'm open to create a new project and push the code there. Don't care >> about the name. Then we might figure out which parts are already good, >> which parts could be improved and where to go next. I think switching to >> JSONB for example will be easy, as it offers the same functions than JSON >> afaik. >> >> >> Gesendet: Dienstag, 30. September 2014 um 21:16 Uhr >> Von: "Adam Brusselback" <adambrusselb...@gmail.com> >> An: "Felix Kunde" <felix-ku...@gmx.de> >> Cc: "pgsql-general@postgresql.org" <pgsql-general@postgresql.org> >> Betreff: Re: [GENERAL] table versioning approach (not auditing) >> >> Felix, I'd love to see a single, well maintained project. For example, I >> just found yours, and gave it a shot today after seeing this post. I found >> a bug when an update command is issued, but the old and new values are all >> the same. The trigger will blow up. I've got a fix for that, but if we >> had one project that more than a handful of people used, stuff like that >> would be quashed very quickly. >> >> I love the design of it by the way. Any idea what it will take to move to >> JSONB for 9.4? >> >> >> On Tue, Sep 30, 2014 at 7:22 AM, Felix Kunde <felix-ku...@gmx.de> >> wrote:Hey >> >> yes i'm adding an additional key to each of my tables. First i wanted to >> use the primary key as one column in my audit_log table, but in some of my >> tables the PK consists of more than one column. Plus it's nice to have one >> key that is called the same over all tables. >> >> To get a former state for one row at date x I need to join the latest >> delta BEFORE date x with each delta AFTER date x. If I would log complete >> rows, this joining part would not be neccessary, but as I usually work with >> spatial databases that have complex geometries and also image files, this >> strategy is too harddisk consuming. >> >> If there are more users following a similar approach, I wonder why we not >> throw all the good ideas together, to have one solution that is tested, >> maintained and improved by more developpers. This would be great. >> >> Felix >> >> >> Gesendet: Montag, 29. September 2014 um 23:25 Uhr >> Von: "Abelard Hoffman" <abelardhoff...@gmail.com[abelardhoff...@gmail.com >> ]> >> An: "Felix Kunde" <felix-ku...@gmx.de[felix-ku...@gmx.de]> >> Cc: "pgsql-general@postgresql.org[pgsql-general@postgresql.org]" < >> pgsql-general@postgresql.org[pgsql-general@postgresql.org]> >> Betreff: Re: [GENERAL] table versioning approach (not auditing) >> >> Thank you Felix, Gavin, and Jonathan for your responses. >> >> Felix & Jonathan: both of you mention just storing deltas. But if you do >> that, how do you associate the delta record with the original row? Where's >> the PK stored, if it wasn't part of the delta? >> >> Felix, thank you very much for the example code. I took a look at your >> table schemas. I need to study it more, but it looks like the way you're >> handling the PK, is you're adding a separate synthethic key (audit_id) to >> each table that's being versioned. And then storing that key along with the >> delta. >> >> So then to find all the versions of a given row, you just need to join >> the audit row with the schema_name.table_name.audit_id column. Is that >> right? The only potential drawback there is there's no referential >> integrity between the audit_log.audit_id and the actual table. >> >> I do like that approach very much though, in that it eliminates the need >> to interrogate the json data in order to perform most queries. >> >> AH >> >> >> >> On Mon, Sep 29, 2014 at 12:26 AM, Felix Kunde <felix-ku...@gmx.de[ >> felix-ku...@gmx.de]> wrote:Hey >> >> i've also tried to implement a database versioning using JSON to log >> changes in tables. Here it is: >> https://github.com/fxku/audit[https://github.com/fxku/audit][https://github.com/fxku/audit[https://github.com/fxku/audit]] >> I've got two versioning tables, one storing information about all >> transactions that happened and one where i put the JSON logs of row changes >> of each table. I'm only logging old values and not complete rows. >> >> Then I got a function that recreates a database state at a given time >> into a separate schema - either to VIEWs, MVIEWs or TABLES. This database >> state could then be indexed in order to work with it. You can also reset >> the production state to the recreated past state. >> >> Unfortunately I've got no time to further work on it at the moment + I >> have not done tests with many changes in the database so I can't say if the >> recreation process scales well. On downside I've realised is that using the >> json_agg function has limits when I've got binary data. It gets too long. >> So I'm really looking forward using JSONB. >> >> There are more plans in my mind. By having a Transaction_Log table it >> should be possible to revert only certain transactions. I'm also thinking >> of parallel versioning, e.g. different users are all working with their >> version of the database and commit their changes to the production state. >> As I've got a unique history ID for each table and each row, I should be >> able to map the affected records. >> >> Have a look and tell me what you think of it. >> >> Cheers >> Felix >> >> >> Gesendet: Montag, 29. September 2014 um 04:00 Uhr >> Von: "Abelard Hoffman" <abelardhoff...@gmail.com[abelardhoff...@gmail.com >> ]> >> An: "pgsql-general@postgresql.org[pgsql-general@postgresql.org]" < >> pgsql-general@postgresql.org[pgsql-general@postgresql.org]> >> Betreff: [GENERAL] table versioning approach (not auditing) >> >> Hi. I need to maintain a record of all changes to certain tables so >> assist in viewing history and reverting changes when necessary (customer >> service makes an incorrect edit, etc.). >> >> I have studied these two audit trigger examples: >> >> https://wiki.postgresql.org/wiki/Audit_trigger[https://wiki.postgresql.org/wiki/Audit_trigger][https://wiki.postgresql.org/wiki/Audit_trigger[https://wiki.postgresql.org/wiki/Audit_trigger]] >> https://wiki.postgresql.org/wiki/Audit_trigger_91plus >> >> I've also read about two other approaches to versioning: >> 1. maintain all versions in one table, with a flag to indicate which is >> the current version >> 2. have a separate versions table for each real table, and insert into >> the associated version table whenever an update or insert is done. >> >> My current implementation is based on the wiki trigger examples, using a >> single table, and a json column to record the row changes (rather than >> hstore). What I like about that, in particular, is I can have a "global," >> chronological view of all versioned changes very easily. >> >> But there are two types of queries I need to run. >> 1. Find all changes made by a specific user >> 2. Find all changes related to a specific record >> >> #1 is simple to do. The versioning table has a user_id column of who made >> the change, so I can query on that. >> >> #2 is more difficult. I may want to fetch all changes to a group of >> tables that are all related by foreign keys (e.g., find all changes to >> "user" record 849, along with any changes to their "articles," "photos," >> etc.). All of the data is in the json column, of course, but it seems like >> a pain to try and build a query on the json column that can fetch all those >> relationships (and if I mess it up, I probably won't generate any errors, >> since the json is so free-form). >> >> So my question is, do you think using the json approach is wrong for this >> case? Does it seem better to have separate versioning tables associated >> with each real table? Or another approach? >> >> Thanks >> >> >> >> >> >> -- >> Sent via pgsql-general mailing list (pgsql-general@postgresql.org[ >> pgsql-general@postgresql.org]) >> To make changes to your subscription: >> >> http://www.postgresql.org/mailpref/pgsql-general[http://www.postgresql.org/mailpref/pgsql-general] > >
