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What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
How do I suspend painting for a control and its children?
...ke to completely prevent it from redrawing while I do that - SuspendLayout and ResumeLayout aren't enough. How do I suspend painting for a control and its children?
...
For loop example in MySQL
...ile v_counter < v_max do
insert into foo (val) values ( floor(0 + (rand() * 65535)) );
set v_counter=v_counter+1;
end while;
commit;
end #
delimiter ;
call load_foo_test_data();
select * from foo order by id;
...
How do I define a method in Razor?
...cality. MVC isn't the only game in town. Some folks just like simple razor and URLRewrite as MVC is a lot to do for little benefit IMO
– Jason Sebring
Oct 28 '12 at 18:00
5
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How to return result of a SELECT inside a function in PostgreSQL?
...ple.
But note the potential naming conflict between the OUT parameter cnt and the column alias of the same name. In this particular case (RETURN QUERY SELECT ...) Postgres uses the column alias over the OUT parameter either way. This can be ambiguous in other contexts, though. There are various way...
How is std::function implemented?
...ed by the compiler creating a class with overloaded function call operator and the referenced variables as members. This suggests that the size of lambda expressions varies, and given enough references variables that size can be arbitrarily large .
...
Objective-C: Property / instance variable in category
...a single storage slot. So if you wanted to use this on multiple instances and have each instance compute a distinct value, it wouldn't work.
Fortunately, the Objective-C runtime has this thing called Associated Objects that can do exactly what you're wanting:
#import <objc/runtime.h>
stati...
Get Substring - everything before certain char
... Some example strings are below. The length of the string before - varies and can be any length
8 Answers
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What's the difference between session.Merge and session.SaveOrUpdate?
...
if the object is versioned (by a <version> or <timestamp>), and the
version property value is the same value assigned to a newly
instantiated object, save() it
otherwise update() the object
and merge() is very different:
if there is a persistent instance with t...
Why isn't vector a STL container?
... &x = b[5]; // that's what really happens
bool y = b[5]; // implicitly converted to bool
assert(b[5] == false); // converted to bool
assert(b[6] == b[7]); // bool operator==(const reference &, const reference &);
b[5] = true; // assignment on reference
assert(b[5] == true); // and actua...