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SQL - many-to-many table primary key
... a separate index on (col2,col1) will catch those cases where the opposite order would execute faster. The surrogate is a waste of space.
You won't need indexes on the individual columns since the table should only ever be used to join the two referenced tables together.
That comment you refer to ...
Calling parent class __init__ with multiple inheritance, what's the right way?
...he other hand, it's easier to make mistakes. For example if you change the order of Foo and Bar (like class FooBar(Bar, Foo)), you'd have to update the super calls to match. Without super you don't have to worry about this, and the code is much more readable.
One of the classes is a mixin.
A mixin...
Setting unique Constraint with fluent API?
...t type unique key combination:
[Index("IX_UniqueKeyInt", IsUnique = true, Order = 1)]
public int UniqueKeyIntPart1 { get; set; }
[Index("IX_UniqueKeyInt", IsUnique = true, Order = 2)]
public int UniqueKeyIntPart2 { get; set; }
If the data type is string, then MaxLength attribute must be added:
...
Is there any advantage of using map over unordered_map in case of trivial keys?
A recent talk about unordered_map in C++ made me realize that I should use unordered_map for most cases where I used map before, because of the efficiency of lookup ( amortized O(1) vs. O(log n) ). Most times I use a map, I use either int or std::string as the key type; hence, I've got...
What are the differences between concepts and template constraints?
...the syntax and semantics of a type.
As an example, consider the following Ordered concept:
concept Ordered<Regular T> {
requires constraint Less<T>;
requires axiom Strict_total_order<less<T>, T>;
requires axiom Greater<T>;
requires axiom Less_equal<T>;
...
WAMP 403 Forbidden message on Windows 7
...amp/www/">
Options Indexes FollowSymLinks
AllowOverride all
Order Deny,Allow
Deny from all
Allow from 127.0.0.1
</Directory>
The same goes for your PHPMyAdmin access, the config file is phpmyadmin.conf :
<Directory "c:/wamp/apps/phpmyadmin3.4.5/">
Options In...
How to urlencode a querystring in Python?
... not always do the trick. The problem is that some services care about the order of arguments, which gets lost when you create the dictionary. For such cases, urllib.quote_plus is better, as Ricky suggested."
– Blairg23
Aug 17 '15 at 21:35
...
Sorting multiple keys with Unix sort
... @Arun POS is explained at the end of the man page. You just append the ordering options to the field number like this: sort -k 3,3nr -k 2,2
– andras
Aug 4 '17 at 15:03
1
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Including all the jars in a directory within the Java classpath
...AR files in a single directory foo, use either
foo;foo/* or foo/*;foo. The order chosen determines whether the
classes and resources in foo are loaded before JAR files in foo, or
vice versa.
Subdirectories are not searched recursively. For example, foo/* looks
for JAR files only in foo, not in foo/b...
custom listview adapter getView method being called multiple times, and in no coherent order
...
This is not an issue, there is absolutely no guarantee on the order in which getView() will be called nor how many times. In your particular case you are doing the worst thing possible with a ListView by giving it a height=wrap_content. This forces ListView to measure a few children out...