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MySQL order by before group by
...t the max(post_date) by author is to use a subquery to return the max date and then join that to your table on both the post_author and the max date.
The solution should be:
SELECT p1.*
FROM wp_posts p1
INNER JOIN
(
SELECT max(post_date) MaxPostDate, post_author
FROM wp_posts
WHERE po...
Android Studio says “cannot resolve symbol” but project compiles
I'm importing twitter4j in AndroidStudio, using the following in my build.gradle:
27 Answers
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What is the difference between Forking and Cloning on GitHub?
I'd like to know the differences between doing a Fork of a project and doing a clone of it.
9 Answers
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Non-static variable cannot be referenced from a static context
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You must understand the difference between a class and an instance of that class. If you see a car on the street, you know immediately that it's a car even if you can't see which model or type. This is because you compare what you see with t...
Schrödingers MySQL table: exists, yet it does not
...er_table, check the data directory to make sure you have both an .frm file and .ibd file for the table in question. If it's MYISAM, there should be a .frm, .MYI and a .MYD file.
The problem can usually be resolved by deleting the orphaned file manually.
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What is the combinatory logic equivalent of intuitionistic type theory?
I recently completed a university course which featured Haskell and Agda (a dependent typed functional programming language), and was wondering if it was possible to replace lambda calculus in these with combinatory logic. With Haskell this seems possible using the S and K combinators, thus making i...
What is the difference between an int and a long in C++?
... (an answer by example) with some of the details below regarding the C++ standard. The draft for C++0x is at open-std.org/JTC1/SC22/WG21/docs/papers/2008/n2798.pdf and it is marked up so you can see the differences between it and the last rev.
– Patrick Johnmeyer
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Is it smart to replace boost::thread and boost::mutex with c++11 equivalents?
... is that my genius project manager thinks that boost is another dependency and that it is horrible because "you depend on it"(I tried explaining the quality of boost, then gave up after some time :( ). Smaller reason why I would like to do it is that I would like to learn c++11 features, because peo...
NULL values inside NOT IN clause
...t I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the con...
Pros and cons to use Celery vs. RQ [closed]
...ect that requires implement some background jobs (mostly for email sending and heavily database updates). I use Redis for task broker. So in this point I have two candidates: Celery and RQ . I had some experience with these job queues, but I want to ask you guys to share you experience of using t...