Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p><strong>Important:</strong> if you only need the one endian, see the pointer magic by wj32 / dtb</p> <hr> <p>Personally, I would be writing directly to a <code>Stream</code> (perhaps with some buffering), and re-using a shared buffer that I can generally assume is clean. Then you can make some shortcuts and assume index 0/1/2/3.</p> <p>Certainly don't use <code>BitConverter</code>, as that can't be used for both little/big-endian, which you require. I would also be inclined to just use bit-shifting rather than unsafe etc. It is actally the fastest, based on the following (so I'm glad that this is how I already do it my code <a href="http://code.google.com/p/protobuf-net/source/browse/branches/v1/protobuf-net/SerializationContext.Write.cs#184" rel="nofollow noreferrer">here</a>, look for <code>EncodeInt32Fixed</code>):</p> <pre><code>Set1: 371ms Set2: 171ms Set3: 993ms Set4: 91ms &lt;==== bit-shifting ;-p </code></pre> <p>code:</p> <pre><code>using System; using System.Diagnostics; using System.Runtime.InteropServices; static class Program { static void Main() { const int LOOP = 10000000, INDEX = 100, VALUE = 512; byte[] buffer = new byte[1024]; Stopwatch watch; watch = Stopwatch.StartNew(); for (int i = 0; i &lt; LOOP; i++) { Set1(buffer, INDEX, VALUE); } watch.Stop(); Console.WriteLine("Set1: " + watch.ElapsedMilliseconds + "ms"); watch = Stopwatch.StartNew(); for (int i = 0; i &lt; LOOP; i++) { Set2(buffer, INDEX, VALUE); } watch.Stop(); Console.WriteLine("Set2: " + watch.ElapsedMilliseconds + "ms"); watch = Stopwatch.StartNew(); for (int i = 0; i &lt; LOOP; i++) { Set3(buffer, INDEX, VALUE); } watch.Stop(); Console.WriteLine("Set3: " + watch.ElapsedMilliseconds + "ms"); watch = Stopwatch.StartNew(); for (int i = 0; i &lt; LOOP; i++) { Set4(buffer, INDEX, VALUE); } watch.Stop(); Console.WriteLine("Set4: " + watch.ElapsedMilliseconds + "ms"); Console.WriteLine("done"); Console.ReadLine(); } unsafe static void Set1(byte[] target, int index, int value) { fixed (byte* p = &amp;target[0]) { Marshal.WriteInt32(new IntPtr(p), index, value); } } unsafe static void Set2(byte[] target, int index, int value) { int* p = &amp;value; for (int i = 0; i &lt; 4; i++) { target[index + i] = *((byte*)p + i); } } static void Set3(byte[] target, int index, int value) { byte[] data = BitConverter.GetBytes(value); Buffer.BlockCopy(data, 0, target, index, data.Length); } static void Set4(byte[] target, int index, int value) { target[index++] = (byte)value; target[index++] = (byte)(value &gt;&gt; 8); target[index++] = (byte)(value &gt;&gt; 16); target[index] = (byte)(value &gt;&gt; 24); } } </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POFastest way of reading and writing binary
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USAdam Baxter
    1. USMarc Gravell
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POFastest way of reading and writing binary
      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. COi don't think Stream would be a good solution, the problem is there may be seeks needed and the data is not always read and writen sequential. Another problem would be endianess..
      singulars
      1. PO
      1. UShaze4real
    2. COFine - don't use the stream; but see `Set4` and the performance evidence...
      singulars
      1. PO
      1. USMarc Gravell
    3. COi need to verify this first and may accept this answer as solution, what about getting/reading?
      singulars
      1. PO
      1. UShaze4real
 

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