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Why would anyone use set instead of unordered_set?
... and many other places. What I understand is that unordered_set is hash table with O(1) lookup complexity. On the other hand, set is nothing but a tree with log(n) lookup complexity. Why on earth would anyone use set instead of unordered_set? i.e is there a need for set anymore?
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“’” showing on page instead of “ ' ”
...h is being decoded as CP-1252 instead of UTF-8. If you check the encodings table, then you see that this character is in UTF-8 composed of bytes 0xE2, 0x80 and 0x99. If you check the CP-1252 code page layout, then you'll see that each of those bytes stand for the individual characters â, € and ...
How do I modify a MySQL column to allow NULL?
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You want the following:
ALTER TABLE mytable MODIFY mycolumn VARCHAR(255);
Columns are nullable by default. As long as the column is not declared UNIQUE or NOT NULL, there shouldn't be any problems.
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SQL Server reports 'Invalid column name', but the column is present and the query works through mana
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I suspect that you have two tables with the same name. One is owned by the schema 'dbo' (dbo.PerfDiag), and the other is owned by the default schema of the account used to connect to SQL Server (something like userid.PerfDiag).
When you have an unquali...
How to create CSV Excel file C#? [closed]
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Its best example...but how can i add two table in single file,means i have a one table of two rows and other table is 10 rows and both have unique column name.I want to add two rows table on top and after gap of two lines i want to add second table.
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What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
... least as much storage as those preceding it in the list.
There's also a table 9 in 7.1.6.2 Simple type specifiers, which shows the "mappings" of the specifiers to actual types (showing that the int is optional), a section of which is shown below:
Specifier(s) Type
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Specifying column name in a “references” migration
I want to make a migration in Rails, referencing another table. Usually, I would do something like:
6 Answers
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Best practice using NSLocalizedString
...calizedString = [[NSBundle mainBundle] localizedStringForKey:key value:key table:nil];
// if (value == key) and comment is not nil -> returns comment
if([localizedString isEqualToString:key] && comment !=nil)
return comment;
return localizedString;
}
@end
3. Use i...
Android Studio/Intellij Idea: “Table of Contents” for a class
...t I have seen. One thing that has been annoying me though is this lack of "Table of Contents" for a class. I apologize for not knowing exactly what to call it. But what I am referring to is the dropdown menu in eclipse that lists all the methods, interfaces, classes and so on that are in that class ...
SQL - find records from one table which don't exist in another
I've got the following two SQL tables (in MySQL):
8 Answers
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