Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>First - most classes will never need to be thread-safe. Use <a href="http://en.wikipedia.org/wiki/You_aren&#39;t_gonna_need_it" rel="noreferrer">YAGNI</a>: only apply thread-safety when you know you actually are going to use it (and test it).</p> <p>For the method-level stuff, there is <code>[MethodImpl]</code>:</p> <pre><code>[MethodImpl(MethodImplOptions.Synchronized)] public void SomeMethod() {/* code */} </code></pre> <p>This can also be used on accessors (properties and events):</p> <pre><code>private int i; public int SomeProperty { [MethodImpl(MethodImplOptions.Synchronized)] get { return i; } [MethodImpl(MethodImplOptions.Synchronized)] set { i = value; } } </code></pre> <p>Note that field-like events <em>are</em> synchronized by default, while auto-implemented properties <em>are not</em>:</p> <pre><code>public int SomeProperty {get;set;} // not synchronized public event EventHandler SomeEvent; // synchronized </code></pre> <p>Personally, I don't like the implementation of <code>MethodImpl</code> as it locks <code>this</code> or <code>typeof(Foo)</code> - which is against best practice. The preferred option is to use your own locks:</p> <pre><code>private readonly object syncLock = new object(); public void SomeMethod() { lock(syncLock) { /* code */ } } </code></pre> <p>Note that for field-like events, the locking implementation is dependent on the compiler; in older Microsoft compilers it is a <code>lock(this)</code> / <code>lock(Type)</code> - however, <a href="http://marcgravell.blogspot.co.uk/2010/03/revisited-fun-with-field-like-events.html" rel="noreferrer">in more recent compilers it uses <code>Interlocked</code></a> updates - so thread-safe without the nasty parts.</p> <p>This allows more granular usage, and allows use of <code>Monitor.Wait</code>/<code>Monitor.Pulse</code> etc to communicate between threads.</p> <p>A related <a href="http://marcgravell.blogspot.com/2009/02/fun-with-field-like-events.html" rel="noreferrer">blog entry</a> (later <a href="http://marcgravell.blogspot.co.uk/2010/03/revisited-fun-with-field-like-events.html" rel="noreferrer">revisited</a>).</p>
    singulars
    1. This table or related slice is empty.
    1. POC# version of java's synchronized keyword?
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USMarc Gravell
    1. USMarc Gravell
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POC# version of java's synchronized keyword?
      singulars
      1. PTQuestion
    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
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. CO@earcam and your question is? That statement is true. The vast majority of classes have no requirement to be thread-safe, will not be tested for thread-safety, and *having* thread-safety will impact performance. The number of types that genuinely need to worry about threads is very small - intentionally synchronized collections, multiplexers, etc.
      singulars
      1. PO
      1. USMarc Gravell
    2. COSorry @Marc, I deleted the comment shortly afterwards (as without explanation it served no purpose but to smell like a troll). I'll repeat here: ""most classes will never need to be thread-safe" eh?" The reason for my "eh?" is that's quite a sweeping statement. I still disagree but perhaps it's just the way you stated it - in my mind you should always be aware of the context your classes will be used in (frameworks etc). Quite agree the number is small, but here critical. Diff design can remove locks completely; immutable classes and guarding shared state through sync'd collections etc.
      singulars
      1. PO
      1. USearcam
    3. CO@earcam indeed I'm very familiar with deeply threaded code... but that is the exception, not the norm - and even then, not all classes involved need to get involved
      singulars
      1. PO
      1. USMarc Gravell
 

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