OrientDB classes / clusters design -

-

i design following using classes , clusters looking logical , efficient solution.

i, have 3 types of users (very different) designed them classes extends user abstract class.

my app based on geoloc. in order give best user experience in matter of response time speed (when performing scans etc..) i'm hesitating between 2 methods :

  1. having each usertype many clusters number of countries, select targetting concerned cluster.

                               _______________________                           | user (abstract class) |                           |_______________________|                                       ^                                       |                                       |  ___________________         ___________________         ___________________ | usertype1 (class) |       | usertype2 (class) |       | usertype3 (class) | |___________________|       |___________________|       |___________________|           |                           |                           |           |                           |                           |     us-cluster_1                us-cluster_2                us-cluster_3     fr-cluster_1                fr-cluster_2                fr-cluster_3     uk-cluster_1                uk-cluster_2                uk-cluster_3

  2. having countryfield each usertype select users filtering it.

                               _______________________                           | user (abstract class) |                           |_______________________|                                       ^                                       |                                       |  ___________________         ___________________         ___________________ | usertype1 (class) |       | usertype2 (class) |       | usertype3 (class) | |                   |       |                   |       |                   | | - countryfield    |       | - countryfield    |       | - countryfield    | |___________________|       |___________________|       |___________________|

    and select * usertype1 countryfield = "us"

what efficient , logical way ?

thank you.

partly depends on record counts , desired response time. in our experience separating data clusters improves query times @ expense of more complexity (managing clusters, different queries, etc.). put couple million records in each cluster , add home-made indexes make query times quick.

you should generate test data , store both ways test query performance vs. requirements. no 2 use-cases ever same.


Comments

Post a Comment

Popular posts from this blog

java - Oracle EBS .ClassNotFoundException: oracle.apps.fnd.formsClient.FormsLauncher.class ERROR -

-
i need in configuring java on machine because, when try loading forms, loader goes in circles , gives error: java.lang.classnotfoundexception: oracle.apps.fnd.formsclient.formslauncher.class @ sun.plugin2.applet.applet2classloader.findclass(unknown source) @ sun.plugin2.applet.plugin2classloader.loadclass0(unknown source) @ sun.plugin2.applet.plugin2classloader.loadclass(unknown source) @ sun.plugin2.applet.plugin2classloader.loadclass(unknown source) @ java.lang.classloader.loadclass(unknown source) @ sun.plugin2.applet.plugin2classloader.loadcode(unknown source) @ sun.plugin2.applet.plugin2manager.createapplet(unknown source) @ sun.plugin2.applet.plugin2manager$appletexecutionrunnable.run (unknown source) @ java.lang.thread.run(unknown source) i have tried re-installing firefox, older versions of java runtime environments, disabling proxy. what missing? application working on other machines. i spent around 100 hours finding s...
Read more

c# - how to use buttonedit in devexpress gridcontrol -

-
Image
i trying create gridcontrol buttonedit in 1 of columns. when user clicks button edit, popups form select product. when selection done on popup, returns datarow selection main grid below. but when column loses focus, value wrote column disappear. here code creates gridcontrol's data , buttonedit's click event. private void frmsiparisnew_load(object sender, eventargs e) { dt = new datatable(); dt.columns.add("malzeme_kodu",typeof(string)); dt.columns.add("malzeme_aciklama", typeof(string)); dt.columns.add("adet", typeof(decimal)); dt.columns.add("birim", typeof(string)); dt.columns.add("fiyat", typeof(decimal)); dt.columns.add("kur", typeof(string)); dt.columns.add("tutar", typeof(decimal)); datarow dr = dt.newrow(); dt.rows.add(dr); gc.datasource = dt; } private void repositoryitembuttoneditmal...
Read more

How do you convert a timestamp into a datetime in python with the correct timezone? -

-
you naively expect work: import pytz datetime import datetime def tz_datetime_from_timestamp(timestamp): """convert timestamp datetime """ tz = pytz.timezone('australia/perth') server_time = datetime.utcnow() delta = tz.utcoffset(server_time) value = datetime.utcfromtimestamp(timestamp).replace(tzinfo=tz) return value + delta print tz_datetime_from_timestamp(1416387060) and convert timestamp 1416387060 wed nov 19 16:51:00 2014 gmt+8:00. ...but not. prints: 2014-11-19 16:51:00+07:43 the timezone of australia/perth not gmt+7:43. it gmt+8:00. unequivocally stated on australian government website http://www.australia.gov.au/about-australia/our-country/time : awst equal coordinated universal time plus 8 hours (utc +8). so, heck pytz pulling 7.43 from? well, turns out pytz pulls data http://www.iana.org/time-zones time zone database, , database states: # western australia # # rule name type in on @...
Read more