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How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
...by Laravel when accessing timestamps. To fix for PostgreSQL, use: DB::raw('now()::timestamp(0)') (reference: postgresql.org/docs/8.1/static/…)
– andrewhl
Aug 11 '14 at 20:37
...
Why can't yield return appear inside a try block with a catch?
...iables in the generated type, so you can freely move code to new methods
Now transform:
try
{
Console.WriteLine("a");
yield return 10;
Console.WriteLine("b");
}
catch (Something e)
{
Console.WriteLine("Catch block");
}
Console.WriteLine("Post");
into (sort of pseudo-code):
case...
App Inventor 2 网络微数据库后台搭建教程 - 自建TinyWebDB服务 · App Inventor 2 中文网
...包，先勾选底部的 “Add python.exe to PATH”，再点 “Install Now”。
装完点 “Close”。
需要 Python 3.8 或更新的版本。已经装过的可以跳过这一步。
A2. 启动服务端
把 tinywebdb-server 文件夹放到容易找到的地方，...
Convert a Git folder to a submodule retrospectively?
...
filter-branch is deprecated nowadays. You can use git clone --filter, but your Git server must be configured to allow filtering, otherwise you'll get warning: filtering not recognized by server, ignoring.
– Matthias Braun
...
Android accelerometer accuracy (Inertial navigation)
...which would be pretty limiting. No one reads the TOS anyway.
Oh, and you know that INS drifts with the rotation of the earth, right? So there's that too. One hour later and you're mysteriously climbing on a 15° slope into space. That's assuming you had an INS capable of maintaining location that l...
Object-orientation in C
..., you use function pointers, and optionally function pointer tables, also known as virtual tables or vtables:
struct base;
struct base_vtable
{
void (*dance)(struct base *);
void (*jump)(struct base *, int how_high);
};
struct base
{
struct base_vtable *vtable;
/* base members */
}...
How can I extract embedded fonts from a PDF as valid font files?
...r example by using XPDF's pdftops (on Windows: pdftops.exe helper program.
Now fonts will be embedded in .pfa (PostScript) format + you can extract them using a text editor.
You may need to convert the .pfa (ASCII) to a .pfb (binary) file using the t1utils and pfa2pfb.
In PDFs there are never .pfm o...
Loop through an array in JavaScript
...e this:
var x = [1,2,3,4].map( function(item) {return item * 10;});
And now x is [10,20,30,40].
You don't have to write the function inline. It could be a separate function.
var item_processor = function(item) {
// Do something complicated to an item
}
new_list = my_list.map(item_process...
SQLAlchemy: What's the difference between flush() and commit()?
... # been flushed yet.
s2.flush() # Now, Foo('B') is in the same state as
# Foo('A') was above.
print 3, s2.query(Foo).all()
s2.rollback() # Foo('B') has not been committed, and rolling
...
@property retain, assign, copy, nonatomic in Objective-C
...mic vs. atomic
- "atomic" is the default. Always use "nonatomic". I don't know why, but the book I read said there is "rarely a reason" to use "atomic". (BTW: The book I read is the BNR "iOS Programming" book.)
readwrite vs. readonly
- "readwrite" is the default. When you @synthesize, both a getter...