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How do I use valgrind to find memory leaks?
...free this pointer?
json_decref(root); //What about this one? Does the order matter?
return 0;
}
This is a simple program: it reads a JSON string and parses it. In the making,
we use library calls to do the parsing for us. Jansson makes the necessary
allocations dynamically since JSON ca...
What's the fastest way to merge/join data.frames in R?
...- data.frame(d1, g1, g2)
library(rbenchmark)
benchmark(replications = 1, order = "elapsed",
merge = merge(d1, d2),
plyr = join(d1, d2),
data.table = {
dt1 <- data.table(d1, key = "x")
dt2 <- data.table(d2, key = "x")
data.frame( dt1[dt2,list(x,y1,y2=dt2$y2)] )
...
How to show all privileges from a user in oracle?
...s connect by prior granted_role = grantee start with grantee = '&USER' order by 1,2,3;
select * from dba_sys_privs where grantee = '&USER' or grantee in (select granted_role from dba_role_privs connect by prior granted_role = grantee start with grantee = '&USER') order by 1,2,3;
select ...
What does 'COLLATE SQL_Latin1_General_CP1_CI_AS' do?
...t can be in any combination of the following, but always specified in this order:
CS = case-sensitive or CI = case-insensitive
AS = accent-sensitive or AI = accent-insensitive
KS = Kana type-sensitive or missing = Kana type-insensitive
WS = width-sensitive or missing = width insensitive
VSS = vari...
MySQL SELECT only not null values
...SELECT DISTINCT (
SELECT title
FROM test
WHERE title IS NOT NULL
ORDER BY id DESC
LIMIT 1
) title, (
SELECT body
FROM test
WHERE body IS NOT NULL
ORDER BY id DESC
LIMIT 1
) body
FROM test
I hope help you.
...
Is there a naming convention for MySQL?
... @rsb2097 Re: point 5 - After adding one column (to the end) the order could become invalid. You shouldn't add any constraint that requires re-ordering the columns as that's an unnecessary overhead.
– Will Sheppard
Aug 21 '18 at 10:26
...
jQuery Selector: Id Ends With?
... I answered the question a long time after an answer was accepted, just in order to add more information for visitors. I hope that people who upvote my answer also upvote the answer to the question.
– Romain Guidoux
Jan 17 '13 at 18:47
...
file_put_contents - failed to open stream: Permission denied
... The webserver does not need to have the permission to execute the file in order to change its content. Those write permissions should only be given to files in that directory.
All other users should not be given any permission.
For directories that do not require to change its files are group per...
How should I ethically approach user password storage for later plaintext retrieval?
...
I am not a lawyer, but consider this. If your supervisor orders you to do something against the interests of the company, such as by exposing them to an easily avoided liability, is it your job to obey or to politely refuse? Yes, they're your boss, but they have a boss of their ow...
How to quickly open a file in Visual Studio 2012
...tches to previously opened file
Ctrl + Shift + -: Does the same in reverse order
Ctrl + Tab: Again switches to previous file
Ctrl + Shift + Tab: Does the same in reverse order
Hold Ctrl and press Tab multiple times: Switches to selected file
Hold Ctrl, press Tab and release Tab, then select fi...