大约有 19,000 项符合查询结果（耗时：0.0424秒） [XML]
insert a NOT NULL column to an existing table
...crosoft SQL server. If you want to perform the same operation on Oracle or MySQL you need to use semicolon ; like that:
ALTER TABLE MY_TABLE ADD STAGE INT NULL;
UPDATE MY_TABLE SET <a valid not null values for your column>;
ALTER TABLE MY_TABLE ALTER COLUMN STAGE INT NOT NULL;
...
SQL Server SELECT INTO @variable?
...not all support TOP 1 as Adrian mentioned. SQL Server / MS Access use TOP, MySQL uses LIMIT, and Oracle uses ROWNUM. See w3schools.com/sql/sql_top.asp for more information.
– Tyler
Jul 7 '17 at 12:08
...
Best way to create custom config options for my Rails app?
...er in config/initializers:
# Rails 2
APP_CONFIG = YAML.load_file("#{RAILS_ROOT}/config/config.yml")[RAILS_ENV]
# Rails 3+
APP_CONFIG = YAML.load_file(Rails.root.join('config/config.yml'))[Rails.env]
If you're using Rails 3, ensure you don't accidentally add a leading slash to your relative confi...
Groovy Shell warning “Could not open/create prefs root node …”
...JDK source code for WindowsPreferences.java. In this class, both nodes userRoot and systemRoot were declared static as in:
/**
* User root node.
*/
static final Preferences userRoot =
new WindowsPreferences(USER_ROOT_NATIVE_HANDLE, WINDOWS_ROOT_PATH);
/**
* System root node.
*/
static fin...
Python Nose Import Error
...
I have a situation where tests work if init.py in root directory - however, I need that file to be there, and import models.<model_name> still is not found. Test is inside a tests/ directory, and the model I'm trying to test is inside models/ directory... any help woul...
How to handle dependency injection in a WPF/MVVM application
...ar container = CreateContainer();
var viewModel = container.Resolve<RootViewModel>();
var window = new MainWindow { DataContext = viewModel };
window.Show();
}
}
This is based around an object graph of view-models rooted at the RootViewModel but you can inject some view-model ...
Glorified classes in the Java language
...ledged status of an enum is include it in a switch statement.
Object - the root of all objects (and I would add its clone and finalize methods are not something you could implement)
References: WeakReference, SoftReference, PhantomReference
Thread - the language doesn't give you a specific instructi...
Remove unnecessary svn:mergeinfo properties
...another way to delete all sub tree svn:mergeinfo properties but not at the root folder (this is needed for branching to work properly).
From the root of the project do:
svn propdel svn:mergeinfo -R
svn revert .
svn ci -m "Removed mergeinfo"
...
How to encrypt/decrypt data in php?
...INARY.
The output value, like the IV, is binary; to store those values in MySQL, consider using BINARY or VARBINARY columns. If this is not an option, you can also convert the binary data into a textual representation using base64_encode() or bin2hex(), doing so requires between 33% to 100% more st...
How to tell git to ignore individual lines, i.e. gitignore for specific lines of code [duplicate]
...of do it with git filters:
Create/Open gitattributes file:
<project root>/.gitattributes (will be committed into repo)
OR
<project root>/.git/info/attributes (won't be committed into repo)
Add a line defining the files to be filtered:
*.rb filter=gitignore, i.e. run filter named g...