Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>Use the caching options built into HttpWebResponse. This lets you programatically choose between obtaining straight from cache (ignoring freshness), ignoring the cache, forcing the cache to be refreshed, forcing the cache to be revalidated and the normal behaviour of using the cache if it's considered fresh according to the original response's age information, and otherwise revalidating it.</p> <p>Even if you've really specific caching requirements that need to go beyond that, build it on top of doing HTTP caching properly, rather than as a complete replacement.</p> <p>If you do need to manage your own cache of the XML streams, then normal file locking and if really necessary, .NET ReaderWriterLockSlims should suffice to keep different threads from messing each other up. One possibility to remove the risk of contention that is too high, is to default to direct access in the case of cache contention. Consider that caching is ultimately an optimisation (conceptually you are getting the file "from the server", caching just makes this happen in a more efficient manner). Hence, if you fail to quickly obtain a read-lock, you can revert to downloading directly. This in turn reduces the wait that can happen for the write lock (because pending locks won't stack up over time while a write lock is requested). In practice it probably won't happen very often, but it will save you from the risk of unacceptable contention building up around one file and bringing the whole system down.</p>
    singulars
    1. This table or related slice is empty.
    1. POWhat is the best way to cache XML feeds locally?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USJon Hanna
    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
    1. COOh, I should add - as it might be relevant here - that another option in dealing with the normal cache is to add on an acceptable degree of staleness, e.g. ("give me this if it's fresh, or if you would normally consider it out of date but out of date by less than 4hours").
      singulars
      1. PO
      1. USJon Hanna
    2. COWould it be possible to check actual size or status of file and if cache/sync only if it differs?
      singulars
      1. PO
      1. USferonovak
    3. COIt would, though you'd have to go further as changes can (and in real life, often do) result in equal-sized files. You could store and MD5 of the file or the E-tag that the WebResponse got (this latter is better if E-tags are being sent; if not berate the person running the web side of things if possible until they are) or the last-mod date on the web response (if sub-second changes are impossible in this system). Again, checking last-mod and etags happens automatically with the appropriate use of the web cache built in to HttpWebResponse when you use appropriate options.
      singulars
      1. PO
      1. USJon Hanna
 

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