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MySQL, better to insert NULL or empty string?
...ome of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
...
Are inline virtual functions really a non-sense?
... as this->Temp::myVirtualFunction() - such invokation skips the virtual table resolution and the function should be inlined without problems - why and if you'd want to do it is another topic :)
– RnR
Apr 9 '09 at 12:12
...
CSS styling in Django forms
...ces; your classes or other attributes just work if you use the Django's as_table/as_ul/as_p form methods. If you need full control for a completely custom rendering, this is clearly documented
-- EDIT 2 ---
Added a newer way to specify widget and attrs for a ModelForm.
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Best way to check if object exists in Entity Framework?
...t.Employees.Any()) Then ' Check if there are "any" records in the Employee table
Dim employee = From c In context.Employees Select c.PayrollNumber ' Select just the PayrollNumber column to work with
For Each item As Object In employee ' Loop through each employee in the Employees ent...
Nested select statement in SQL Server
... as a
We need to make an alias of the subquery because a query needs a table object which we will get from making an alias for the subquery. Conceptually, the subquery results are substituted into the outer query. As we need a table object in the outer query, we need to make an alias of the inne...
PostgreSQL delete with inner join
...
for larger tables, the first solution in this answer is potentially much faster.
– mgoldwasser
Nov 2 '14 at 16:58
2
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How many GCC optimization levels are there?
...is a strong indicator that there are only 3 levels.
opts.c:default_options_table
opt_levels is so interesting, that we grep OPT_LEVELS_3_PLUS, and come across opts.c:default_options_table:
static const struct default_options default_options_table[] = {
/* -O1 optimizations. */
{ OPT_LEVELS_...
Error: 10 $digest() iterations reached. Aborting! with dynamic sortby predicate
...controller="testctrl">
<label>{{total}}</label>
<table>
<tr ng-repeat="item in items track by $index;" ng-init="end($index);">
<td>{{item.number}}</td>
</tr>
</table>
</div>
var app = angular.module('myApp',...
Submitting a multidimensional array via POST with php
...p through the values.
if ( isset( $_POST['diameters'] ) )
{
echo '<table>';
foreach ( $_POST['diameters'] as $diam )
{
// here you have access to $diam['top'] and $diam['bottom']
echo '<tr>';
echo ' <td>', $diam['top'], '</td>';
e...
Entity Framework: “Store update, insert, or delete statement affected an unexpected number of rows (
...he scenes, but I don't have any extra code of my own that is modifying the tables. Is there a way to change this concurrency setting?
– strongopinions
Dec 4 '09 at 0:16
3
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