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Reliable method to get machine's MAC address in C#
...aces()
where nic.OperationalStatus == OperationalStatus.Up
select nic.GetPhysicalAddress().ToString()
).FirstOrDefault();
Or:
String firstMacAddress = NetworkInterface
.GetAllNetworkInterfaces()
.Where( nic => nic.OperationalStatus == OperationalStatus.Up &&...
Finding duplicate values in MySQL
...
Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
Overloaded method selection based on the parameter's real type
...
I expect the method selection to take
in consideration the real (not the
declared) parameter type. Am I missing
something?
Yes. Your expectation is wrong. In Java, dynamic method dispatch happens only for the object the method is called ...
What's the purpose of SQL keyword “AS”?
...ynes Yes. Just concatenate (||) the columns and then give it an alias e.g. SELECT foo || bar AS foobar.
– Rupert Madden-Abbott
Dec 10 '18 at 14:26
...
Equals(=) vs. LIKE
... can produce results different from the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLATE latin1_german2_ci;
+-----------------------------------------+
| 'ä' LIKE 'ae' COLLATE latin1_german2_ci |
+-----------------------------------------+
| 0 |...
Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
Insert, on duplicate update in PostgreSQL?
...try the UPDATE again
END;
END LOOP;
END;
$$
LANGUAGE plpgsql;
SELECT merge_db(1, 'david');
SELECT merge_db(1, 'dennis');
There's possibly an example of how to do this in bulk, using CTEs in 9.1 and above, in the hackers mailing list:
WITH foos AS (SELECT (UNNEST(%foo[])).*)
updated...
Hidden Features of Xcode
...m working with a large or unfamiliar project.
To show the Favorites Bar, select the following menu option:
View > Layout > Show Favorites Bar
share
edited Apr 4 '11...
How to select the last record of a table in SQL?
This is a sample code to select all records from a table. Can someone show me how to select the last record of that table?
...
Why does the jquery change event not trigger when I set the value of a select using val()?
... not being run when the value is set by val() , but it does run when user selects a value with their mouse. Why is this?
9...