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SQL Server Profiler - How to filter trace to only display events from one database?
...lumn and find out the correct values to enter by querying the sysdatabases table in the master database
– Jim Birchall
Nov 10 '08 at 8:39
35
...
MAC addresses in JavaScript
...ince any server-side programming language allows you do get access the ARP table, even indirectly (e.g. through a subprocess). I think "client-side language" would work better...
– kirbyfan64sos
Oct 6 '16 at 19:51
...
Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column.
...
How do Python's any and all functions work?
....
all
all will return True only when all the elements are Truthy.
Truth table
+-----------------------------------------+---------+---------+
| | any | all |
+-----------------------------------------+---------+---------+
| All Truthy values ...
Get top n records for each group of grouped results
...fy the group number and add queries for each group:
(
select *
from mytable
where `group` = 1
order by age desc
LIMIT 2
)
UNION ALL
(
select *
from mytable
where `group` = 2
order by age desc
LIMIT 2
)
There are a variety of ways to do this, see this article to determine the...
How to do associative array/hashing in JavaScript
...ash/AS3 Dictionary does. In JavaScript, var obj1 = {}; var obj2 = {}; var table= {}; table[obj1] = "A"; table[obj2] = "B"; alert(table[obj1]); //displays B, because it can't differentiate between keys obj1 and obj2; they're both converted to string and just become something like "Object". Total fa...
how to iterate through dictionary in a dictionary in django template?
...d values[0] does not work, if that is the case then try values.items.
<table>
<tr>
<td>a</td>
<td>b</td>
<td>c</td>
</tr>
{% for key, values in data.items %}
<tr>
<td>{{key}}</td>...
How to read data from a zip file without having to unzip the entire file
...can also extract to a file or other destinations).
Reading the zip file's table of contents is as easy as:
using (ZipFile zip = ZipFile.Read(ExistingZipFile))
{
foreach (ZipEntry e in zip)
{
if (header)
{
System.Console.WriteLine("Zipfile: {0}", zip.Name);
if ((zip.Comment ...
Algorithm to detect corners of paper sheet in photo
...nes within a certain tolerance to those.
My grouping worked as a look up table, for each line outputted from the hough transform it would give a rho and theta pair. If these values were within, say 5% of a pair of values in the table, they were discarded, if they were outside that 5%, a new entry ...
How to convert char to int?
...appens.
A Char, is basically an integer, but with a pointer in the ASCII table. All characters have a corresponding integer value as you can clearly see when trying to parse it.
Pranay has clearly a different character set, thats why HIS code doesnt work.
the only way is
int val = '1' - '0';
...
