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Difference between 'struct' and 'typedef struct' in C++?
... It's a holdover from C, in which it makes a difference.
The C language standard (C89 §3.1.2.3, C99 §6.2.3, and C11 §6.2.3) mandates separate namespaces for different categories of identifiers, including tag identifiers (for struct/union/enum) and ordinary identifiers (for typedef and other iden...
How do I execute a stored procedure once for each row returned by query?
...stored procedure that alters user data in a certain way. I pass it user_id and it does it's thing. I want to run a query on a table and then for each user_id I find run the stored procedure once on that user_id
...
Node.js check if path is file or directory
...fs.lstatSync(path_string).isDirectory()
Objects returned from fs.stat() and fs.lstat() are of this type.
stats.isFile()
stats.isDirectory()
stats.isBlockDevice()
stats.isCharacterDevice()
stats.isSymbolicLink() (only valid with fs.lstat())
stats.isFIFO()
stats.isSocket()
NOTE:
The above solutio...
How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
MyISAM versus InnoDB [closed]
... a projects which involves a lot of database writes, I'd say ( 70% inserts and 30% reads ). This ratio would also include updates which I consider to be one read and one write. The reads can be dirty (e.g. I don't need 100% accurate information at the time of read).
The task in question will be ...
Detailed 500 error message, ASP + IIS 7.5
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I have come to the same problem and fixed the same way as Alex K.
So if "Send Errors To Browser" is not working set also this:
Error Pages -> 500 -> Edit Feature Settings -> "Detailed Errors"
Also note that if the content of the error page sen...
How Drupal works? [closed]
...it's procedural PHP it's purely event/listener driven in its architecture, and there's no simple "flow" in the main PHP script for you to look though. I recently did a presentation on this very subject, and the slides are posted on slideshare, but a quick high-level summary may be useful.
Drupal's...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
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MySQL Error 1215: Cannot add foreign key constraint
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I'm guessing that Clients.Case_Number and/or Staff.Emp_ID are not exactly the same data type as Clients_has_Staff.Clients_Case_Number and Clients_has_Staff.Staff_Emp_ID.
Perhaps the columns in the parent tables are INT UNSIGNED?
They need to be exactly the same...
Is it Linq or Lambda?
...ice by allowing you to express your wishes in the manner that you prefer.
And this is a lambda:
x => x.Value == 1
When you choose to use method syntax, LINQ is almost always seen around lambda expressions. But LINQ and lambdas are two totally different things, both of which can be used by the...