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Cron job every three days
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The answer is not correct because neither suggestion actually runs the job every 3 days. 0 0 */3 * * means run on the 1st, 4th, 7th, etc. (*/3 means 1-31/3 means 1,4,7...31) so the gap will be smaller at the end of the month. (It'll run 2 days in a row if the previous month had 3...
What does void* mean and how to use it?
...a pointer to a function that compares two elements of the array. It gets called like so:
int iArr[10];
double dArr[30];
long lArr[50];
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qsort(iArr, sizeof iArr/sizeof iArr[0], sizeof iArr[0], compareInt);
qsort(dArr, sizeof dArr/sizeof dArr[0], sizeof dArr[0], compareDouble);
qsort(lArr, sizeof...
Want to find records with no associated records in Rails
...).where( :friends => { :person_id => nil } )
For the hmt it's basically the same thing, you rely on the fact that a person with no friends will also have no contacts:
Person.includes(:contacts).where( :contacts => { :person_id => nil } )
Update
Got a question about has_one in the c...
What does = +_ mean in JavaScript
I was wondering what the = +_ operator means in JavaScript. It looks like it does assignments.
12 Answers
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C/C++ line number
...processor variables :
__func__ : function name (this is part of C99, not all C++ compilers support it)
__DATE__ : a string of form "Mmm dd yyyy"
__TIME__ : a string of form "hh:mm:ss"
Your code will be :
if(!Logical)
printf("Not logical value at line number %d in file %s\n", __LINE__, __FIL...
mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
... advice about how to properly catch errors in future, it should (IMHO) actually answer the specific question (ie explain why there's an error in this case).
– Sepster
Apr 23 '13 at 22:17
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Using pg_dump to only get insert statements from one table within database
I'm looking for a way to get all rows as INSERT statements from one specific table within a database using pg_dump in PostgreSQL.
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How to delete SQLite database from Android programmatically
...like to delete the database file from the Android file system programatically? Can I have a shell script launch adb which in turns runs a shell script in the Android space to do the database deletion? Can I get this done from within a JUnit test case (with a system() call)?
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How to add http:// if it doesn't exist in the URL?
...hat went on a swim and came back as a fish with the mindset to stop you at all costs from doing and things that might hurt you. There are so many people in the world, and you know, you have this incredible ideas and what you think is missing is motivation, But that is not true. because the way that ...
Why does !{}[true] evaluate to true in JavaScript?
...undefined) must therefore be defined. If something is defined then it's usually interpreted as true.
– OozeMeister
Oct 31 '13 at 16:50
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