大约有 40,000 项符合查询结果（耗时：0.0694秒） [XML]
ALTER TABLE, set null in not null column, PostgreSQL 9.1
I have a table with not null column, How to set a null value in this column as default?
4 Answers
...
Using smart pointers for class members
...ointed to by your (smart) pointer.
Is it going to be the instance of the Settings object alone? Will the Device object have to be destroyed automatically when the Settings object gets destroyed, or should it outlive that object?
In the first case, std::unique_ptr is what you need, since it makes...
JavaScript - cannot set property of undefined
...
you never set d[a] to any value.
Because of this, d[a] evaluates to undefined, and you can't set properties on undefined.
If you add d[a] = {} right after d = {} things should work as expected.
Alternatively, you could use an object...
Where are my postgres *.conf files?
...values can be found in the PostgreSQL documentation.
#
# The commented-out settings shown in this file represent the default values.
# Re-commenting a setting is NOT sufficient to revert it to the default value;
# you need to reload the server.
#
# This file is read on server startup and when the se...
Cell spacing in UICollectionView
How do I set cell spacing in a section of UICollectionView ? I know there is a property minimumInteritemSpacing I have set it to 5.0 still the spacing is not appearing 5.0. I have implemented the flowout delegate method.
...
Set the selected index of a Dropdown using jQuery
How do I set the index of a dropdown in jQuery if the way I'm finding the control is as follows:
9 Answers
...
How to set username and password for SmtpClient object in .NET?
...eb.config, one specifies the host, and one the host and port. But how do I set the username and password to something different from the web.config? We have the issue where our internal smtp is blocked by some high security clients and we want to use their smtp server, is there a way to do this from...
What does @@variable mean in Ruby?
...#{x.value}" # 3
You can see that @@shared is shared between the classes; setting the value in an instance of one changes the value for all other instances of that class and even child classes, where a variable named @shared, with one @, would not be.
[Update]
As Phrogz mentions in the comments, ...
Difference between git checkout --track origin/branch and git checkout -b branch origin/branch
...ambiguation, even if the <branch> isn't unique across all remotes.
Set it to e.g. checkout.defaultRemote=origin to always checkout remote branches from there if <branch> is ambiguous but exists on the 'origin' remote.
Here, '-c' is the new '-b'.
First, some background: Tracking me...
iOS multiline label in Interface builder
...hich defines maximum number of lines a label can have. By default, it's 1. Setting it to 0 means the label will have unlimited lines.
You can do it in code:
textLabel.numberOfLines = 5 // for example
Or in Interface Builder:
...