Rails design for database record (employment) history -

-

so, have rails application tracks employees. want track employment history on time. we'd able following sorts of queries:

  1. search employees current status (salary, manager, title etc.)
  2. search remployees status of particular date
  3. search employees ever matched condition

we don't mind historical queries being slower, maybe 2 orders of magnitude slower.

this history different audit trail - audit trail history of data, audit trail tell "what salary stored employee x on date y," won't let correct older data if wrong.

[we using audit trails auditing purposes, think of logic audit trails providing orthogonal design requirement.]

is there known database design pattern best implementing kind of history? or site can find discussions of various "obvious" designs , trade-offs? rails plugins?

rails 2.3.5 ruby 1.8.7, if matters.

i haven't used it, paper_trail claims support type of version management. seem handle requirements (1) , (2) -- not sure (3), might need heavy lifting query searched across models , versions @ same time.

this history different audit trail

meaning need ability make changes old versions -- doubt supported, , seems problematic implement if need act audit trail.


Comments

Post a Comment

Popular posts from this blog

java - SNMP4J General Variable Binding Error -

-
i trying use snmp4j snmp bulkget. when ever use snmp4j make call returned responseevent error says "general variable binding error" , data returned equal null. to debug: print out, console, exact oid , version number using in snmp4j. use printed out data snmpwalk on command line. valid results. know sending snmp4j correct pdu correct oid, version number, max repititions, etc. i have used snmp4j , code wrote succesffuly monitor other devices years. don't know different time. leaving me stumped. why "general variable binding error?" causes error? ideas debug? can reproduced? if so, first action should using wireshark or microsoft network monitor capture network packets. my guess agent gives generr response, not surprising, http://www.ietf.org/rfc/rfc1157.txt
Read more

windows - Python Service Installation - "Could not find PythonClass entry" -

-
i working on building python service. inducing error, not sure inducing it. ps c:\...> python .\file.py debug debugging service myservice - press ctrl+c stop. error 0xc00000f4 - not find service's pythonclass entry in registry error 1814 - specified resource name cannot found in image file. error 0xc0000080 - not locate module name in python class string (ie, no '.') this error coming pythonservicemessages.mc in pythonwin32. it turns out error result caused exception being thrown , python script dying off.
Read more

Determine if a XmlNode is empty or null in C#? -

-
the following code takes xmlnode data type , populates dataset object xmlnode content. write dataset's content file. public void populatedataset(xmlnode node) { xmlnodereader reader = new xmlnodereader(node); dataset ds = new dataset(); ds.readxml(reader); system.guid guid = system.guid.newguid(); string name = string.format("{0}{1}_{2}.xml", utility.xmloutputpath, utility.xmloutputfilename, guid.tostring()); //need write "node empty" file if xmlnode object empty of null ds.writexml(name, xmlwritemode.ignoreschema); } the problem encountered 1 scenario not write content file. how determine if xmlnode object null or empty? you can check if node parameter null or has innertext or innerxml properties null or empty, when enter method before creating xmlnodereader .
Read more