Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>You can't resize an existing array, however, you can use:</p> <pre><code>Array.Resize(ref arr, newSize); </code></pre> <p>This allocates a new array, copies the data from the old array into the new array, and updates the <code>arr</code> variable (which is passed by-ref in this case). Is that what you mean?</p> <p>However, any <em>other</em> references still pointing at the old array will not be updated. A better option might be to work with <code>List&lt;T&gt;</code> - then you don't need to resize it manually, and you don't have the issue of out-of-date references. You just <code>Add</code>/<code>Remove</code> etc. Generally, you don't tend to use arrays directly very often. They have their uses, but they aren't the default case.</p> <hr> <p>Re your comments;</p> <ul> <li>boxing: <code>List&lt;T&gt;</code> doesn't box. That is one of the points about generics; under the hood, <code>List&lt;T&gt;</code> is a wrapper around <code>T[]</code>, so a <code>List&lt;int&gt;</code> has an <code>int[]</code> - no boxing. The older <code>ArrayList</code> is a wrapper around <code>object[]</code>, so that <em>does</em> box; of course, boxing <a href="http://msmvps.com/blogs/jon_skeet/archive/2008/10/08/why-boxing-doesn-t-keep-me-awake-at-nights.aspx" rel="nofollow noreferrer">isn't as bad as you might assume</a> anyway.</li> <li>workings of <code>Array.Resize</code>; <s>if I recall, it finds the size of <code>T</code>, then uses <code>Buffer.BlockCopy</code> to blit the contents</s> the actual details are hidden by an internal call - but essentially after allocating a new array it is a blit (memcpy) of the data between the two arrays, so it should be pretty quick; note that for reference-types this only copies the reference, not the object on the heap. However, if you are resizing regularly, <code>List&lt;T&gt;</code> would usually be a lot simpler (and quicker unless you basically re-implement what <code>List&lt;T&gt;</code> does re spare capacity to minimise the number of resizes).</li> </ul>
    singulars
    1. This table or related slice is empty.
    1. POWhat are the implications of performing a shallow copy on an array in order to resize it?
      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. POWhat are the implications of performing a shallow copy on an array in order to resize it?
      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. COLet me know if I've misunderstood the question...
      singulars
      1. PO
      1. USMarc Gravell
    2. COSome valid points, but i am specifically looking at arrays. I don't want the overhead incurred from objects that box arrays such as lists. Do you have any details on the inner workings of the Array.Resize method? ie is it very fast?
      singulars
      1. PO
      1. USAdam Naylor
 

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