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Wolfram's Rule 34 in XKCD [closed]
...1110. The digit of least significance is zero. This means that if the cell and its neighbors match rule 0 above, it turns white/negative/0/false/whatever. The second least significant digit is one, so if the cell and its neighbors match rule 1 above, it turns black/positive/1/true/whatever`, etc. et...
Using LIMIT within GROUP BY to get N results per group?
...T aggregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?
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Which particular version of Ubuntu is this and is this Ubuntu Server Edition?
Recent Ubuntu Server Editions (such as 10.04) ship with AppArmor and MySQL's profile might be in enforcing mode by default. You can check this by executing sudo aa-status like so:
# sudo a...
When should I use Kruskal as opposed to Prim (and vice versa)?
I was wondering when one should use Prim's algorithm and when Kruskal's to find the minimum spanning tree? They both have easy logics, same worst cases, and only difference is implementation which might involve a bit different data structures. So what is the deciding factor?
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Best way to get identity of inserted row?
...rns the last identity value generated for any table in the current session and the current scope. Generally what you want to use.
IDENT_CURRENT('tableName') returns the last identity value generated for a specific table in any session and any scope. This lets you specify which table you want the v...
What is the difference between a shim and a polyfill?
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A shim is any piece of code that performs interception of an API call and provides a layer of abstraction. It isn't necessarily restricted to a web application or HTML5/CSS3.
A polyfill is a type of shim that retrofits legacy browsers with modern HTML5/CSS3 features usually using Javascript or ...
visual studio not remembering open documents & startup project
For the past week, something has changed about my VS solution, and I havent found a setting to fix it yet.
16 Answers
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How to choose the id generation strategy when using JPA and Hibernate
I was going through Id generation section of the Hibernate reference guide and "java persistence with Hibernate"
4 Answers
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How to Deep clone in javascript
...first, a code example which clones object literals, any primitives, arrays and DOM nodes.
function clone(item) {
if (!item) { return item; } // null, undefined values check
var types = [ Number, String, Boolean ],
result;
// normalizing primitives if someone did new String('a...
C++ performance challenge: integer to std::string conversion
...e very fast, can take 100 clockticks when linking CRT as a static library, and as much as 300 clockticks when linking as a DLL.
For the same reason, returning by reference is better because it avoids an assignment, a constructor and a destructor.
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