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How to select the first element with a specific attribute using XPath
The XPath bookstore/book[1] selects the first book node under bookstore .
9 Answers
...
Warning as error - How to rid these
...h of your projects and change that setting:
Right-click on your project, select "Properties".
Click "Build".
Switch "Treat warnings as errors" from "All" to "Specific warnings" or "None".
The location of this switch varies, depending on the type of project (class library vs. web application, for...
Maven error “Failure to transfer…”
...ed.properties).
Then go back into Eclipse, Right-click on the project and select Maven > Update Project. I selected to "Force Update of Snapshots/Releases". Click Ok and the dependencies finally resolved correctly.
shar...
Convert Unix timestamp into human readable date using MySQL
...
Use FROM_UNIXTIME():
SELECT
FROM_UNIXTIME(timestamp)
FROM
your_table;
See also: MySQL documentation on FROM_UNIXTIME().
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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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Length of an integer in Python
...h of an integer.
def libc_size(i):
return libc.snprintf(buf, 100, c_char_p(b'%i'), i) # equivalent to `return snprintf(buf, 100, "%i", i);`
def str_size(i):
return len(str(i)) # Length of `i` as a string
def math_size(i):
return 1 + math.floor(math.log10(i)) # 1 + floor of log10 of ...
IntelliJ IDEA: Move line?
... class
Click on relevant class (Red color field) and press,
Alt + Enter
Select valid class as per requirement
(8) Hierarchy of method calls
Select specific method and press,
Ctrl + Alt + H
(9) Comment In Code
Single Line : Select specific line and press,
Ctrl + /
Multiple Line : Select...
How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
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Can I have multiple Xcode versions installed?
... explicitly specify it at install time. Also, you will generally want to unselect all features besides the xcode core tools, because the others don't let you change the install directory.
– Paul Du Bois
Jul 3 '11 at 3:30
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How to select unique records by SQL
When I perform "SELECT * FROM table" I got results like below:
8 Answers
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