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MySQL: Large VARCHAR vs. TEXT?
I've got a messages table in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserte...
How do I create a unique constraint that also allows nulls?
...
This very problem hits ADO.NET DataTables too. So even that I can allow nulls in the backing field using this method, the DataTable won't let me store NULLs in a unique column in the first place. If anyone knows a solution for that, please post it here
...
What is @RenderSection in asp.net MVC
...p>
<a asp-action="Create">Create New</a>
</p>
<table class="table">
<thead>
// do something ...
</thead>
<tbody>
// do something ...
</tbody>
</table>
//Added my custom scripts in the scripts sections
@...
Performance of FOR vs FOREACH in PHP
..._arr1 = array();
$test_arr2 = array();
$test_arr3 = array();
// hash tables
$test_arr4 = array();
$test_arr5 = array();
for ($i = 0; $i < $test_arr_size; ++$i)
{
mt_srand();
$hash = md5(mt_rand());
$key = substr($hash, 0, 5).$i;
$test_arr1[$i] = $test_arr2[$i] = $t...
When to use UICollectionView instead of UITableView?
I found that UICollectionView is like an upgraded version of UITableView introduced in iOS6, but when should I choose UICollectionView instead of UITableView ?
...
Difference between partition key, composite key and clustering key in Cassandra?
...neral concept to indicate one or more columns used to retrieve data from a Table.
The primary key may be SIMPLE and even declared inline:
create table stackoverflow_simple (
key text PRIMARY KEY,
data text
);
That means that it is made by a single column.
But the primary ke...
How to think in data stores instead of databases?
...trained my mind to think 100% in object relationships that map directly to table structures, and now it's hard to see anything differently. I can understand some of the benefits of Google Datastore (e.g. performance and the ability to distribute data), but some good database functionality is sacrif...
Ruby on Rails - Import Data from a CSV file
I would like to import data from a CSV file into an existing database table. I do not want to save the CSV file, just take the data from it and put it into the existing table. I am using Ruby 1.9.2 and Rails 3.
...
How to check if a stored procedure exists before creating it
...ything after AS:
BEGIN
DECLARE @myvar INT
SELECT *
FROM mytable
WHERE @myvar ...
END
This code does exactly same things a stored proc would do, but is not stored on the database side.
That's much like what is called anonymous procedure in PL/SQL.
Update:
Your question tit...
CSS3 transform not working
...evel or atomic inline-level element, or whose display property computes to table-row, table-row-group, table-header-group, table-footer-group, table-cell, or table-caption
an element in the SVG namespace and not governed by the CSS box model which has the attributes transform, ‘patternTransform‘...