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How to stop Visual Studio from opening a file on single click?
...anted to add that the button David is referring to has a tooltip: "Preview Selected Items"
– Bruce van der Kooij
Jan 11 '13 at 9:39
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MySQL - Rows to Columns
...ms that I'll use for the rest of this post. This will be the base table:
select * from history;
+--------+----------+-----------+
| hostid | itemname | itemvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9...
Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...
How do you set the startup page for debugging in an ASP.NET MVC application?
...he start page property.
Go to the project's Properties
Go to the Web tab
Select the Specific Page radio button
Type in the desired url in the Specific Page text box
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iTerm2: How to expand split pane temporarily?
...
@Alper Go to Preferences > Keys > Action > Select Menu Item > View > Maximize Active Pane and enter a custom shortcut.
– Qaz
Dec 14 '17 at 0:13
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Using column alias in WHERE clause of MySQL query produces an error
... though, by putting the expression directly into the WHERE x IN y clause:
SELECT `users`.`first_name`,`users`.`last_name`,`users`.`email`,SUBSTRING(`locations`.`raw`,-6,4) AS `guaranteed_postcode`
FROM `users` LEFT OUTER JOIN `locations`
ON `users`.`id` = `locations`.`user_id`
WHERE SUBSTRING(`loca...
SQLite: How do I save the result of a query as a CSV file?
... file output.
sqlite> .mode csv
sqlite> .output test.csv
sqlite> select * from tbl1;
sqlite> .output stdout
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Returning a C string from a function
...you about that return line converting a char * to char without an explicit cast.
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Cannot ping AWS EC2 instance
...ICMP rule
Protocol: Echo Request
Port: N/A
Source: your choice (I would select Anywhere to be able to ping from any machine)
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Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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