Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>You might enjoy the decade-old but still relevant classic <a href="http://perl.apache.org/docs/tutorials/apps/scale_etoys/etoys.html" rel="nofollow">Building a Large-Scale E-commerce site with Apache and mod_perl</a>. Their tiers were:</p> <ol> <li>Load balancers</li> <li>Reverse proxies</li> <li>Web/app servers</li> <li>Database servers</li> </ol> <p>This is still the blueprint for large-scale sites. Even larger web-scale sites may need something more arcane, but this is the foundation for understanding even them.</p> <p>Note that they used mod_perl, which means their web servers were their app servers. If you were using Java at that time, you would have run the app servers as a tier behind the web servers (and by 'web servers' i mean Apache, handling HTTP parsing, TLS, and static files; fetching and carrying, but no logic), and connected them with AJP. You might still do that today, but you would be more likely to just use the app servers as your web servers (ie no Apache at all, just JBoss or similar). App servers are now solid enough to do this, and you can rely on the reverse proxies and a content distribution network to do most of the fetching and carrying anyway.</p> <p>As for a caching tier, the reverse proxies are a caching tier in front of the app servers, but they did app-level caching on the app server machines, with a federated cache (you'd use memcached or similar for this today). I think that's still a viable option today. I don't see a reason to partition your app-tier servers into dedicated app and cache servers; i'd be interested to hear of reasons to do that.</p> <p>I don't think splitting the presentation and business logic in the app tier is an idea that ever really took off. Some projects probably do it, but i would imagine because of they have architecture astronauts in charge, rather than for any good reason. That said, it is common to have an app tier that makes heavy use of service tiers further back (this is SOA, i guess), and the ultimate extension of that is essentially a presentation/logic split, but with heterogenous logic servers, and the presentation server very much being in charge.</p>
    singulars
    1. This table or related slice is empty.
    1. PON-tier architectural patterns for web apps
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USTom Anderson
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload