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You can't specify target table for update in FROM clause
...you should only be selecting the columns you need in that innermost query, and adding a good WHERE clause to limit the results, too.
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Building a minimal plugin architecture in Python
...ne is, basically, a directory called "plugins" which the main app can poll and then use imp.load_module to pick up files, look for a well-known entry point possibly with module-level config params, and go from there. I use file-monitoring stuff for a certain amount of dynamism in which plugins are a...
Node.js or Erlang
I really like these tools when it comes to the concurrency level it can handle.
9 Answers
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Unnecessary curly braces in C++?
...ould not do this until C99. :)
Since C++ has destructors, it can also be handy to have resources (files, mutexes, whatever) automatically released as the scope exits, which can make things cleaner. This means you can hold on to some shared resource for a shorter duration than you would if you grabb...
SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER joins in ...
Using i and j as variables in Matlab
i and j are very popular variable names (see e.g., this question and this one ).
9 Answers
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How do I map lists of nested objects with Dapper
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Dapper is not a full blown ORM it does not handle magic generation of queries and such.
For your particular example the following would probably work:
Grab the courses:
var courses = cnn.Query<Course>("select * from Courses where Category = 1 Order by Creatio...
Database Design for Revisions?
...tribute. This just causes problems down the line, requires surrogate keys and all sorts of other problems.
Design 2 does have problems with schema changes. If you change the Employees table you have to change the EmployeeHistories table and all the related sprocs that go with it. Potentially doub...
C语言结构体里的成员数组和指针 - c++1y / stl - 清泛IT社区，为创新赋能！
...de <stdio.h>
struct str{
int len;
char s[0];
};
struct foo {
struct str *a;
};
int main(int argc, char** argv) {
struct foo f={0};
if (f.a->s) {
printf( f.a->s);
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An invalid form control with name='' is not focusable
...runs into the problem of an inaccessible form as one can't submit the form and doesn't get any message from the browser or site. Preventing validation altogether via 'novalidate' is no correct answer as clientside validation should support user inputs. Changing the website is the solution.
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