大约有 40,000 项符合查询结果（耗时：0.0852秒） [XML]
How to add column if not exists on PostgreSQL?
...statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THEN RAISE NOTICE 'column <column_name> already exists in <table_name>.';
END;
END;
$$
...
PHP code is not being executed, instead code shows on the page
...guration, here are a few things you can check:
Make sure that PHP is installed and running correctly. This may sound silly, but you never know. An easy way to check is to run php -v from a command line and see if returns version information or any errors.
Make sure that the PHP module is listed an...
How to create SBT project with IntelliJ Idea?
...Sbt developing, and I'd like to import a Sbt project in IntelliJ Idea.
Actually, I managed to import my project in two different ways:
...
QuotaExceededError: Dom exception 22: An attempt was made to add something to storage that exceeded
...ode browsing. While in private browsing, local storage is not available at all.
One solution is to warn the user that the app needs non-private mode to work.
UPDATE: This has been fixed in Safari 11, so the behaviour is now aligned with other browsers.
...
How can I implement an Access Control List in my Web MVC application?
...ion, the best way to approach this would be to use decorator pattern, Basically, this means that you take your object, and place it inside another object, which will act like a protective shell. This would NOT require you to extend the original class. Here is an example:
class SecureContainer
{
...
Set up adb on Mac OS X
... it up might be useful to some people. adb is the command line tool to install and run android apps on your phone/emulator
...
Read error response body in Java
...ere is to code like this:
HttpURLConnection httpConn = (HttpURLConnection)_urlConnection;
InputStream _is;
if (httpConn.getResponseCode() < HttpURLConnection.HTTP_BAD_REQUEST) {
_is = httpConn.getInputStream();
} else {
/* error from server */
_is = httpConn.getErrorStream();
}
...
Keyboard shortcut to change font size in Eclipse?
...d Fonts preference page, the commands persistently change the font size in all editors of the same type. If the editor type's font is configured to use a default font, then that default font will be zoomed.
So, the font size change is not limited to the current file and the new value of the font s...
Enum type constraints in C# [duplicate]
What is the reason behind C# not allowing type constraints on Enum 's? I'm sure there is a method behind the madness, but I'd like to understand why it's not possible.
...
CSV new-line character seen in unquoted field error
...csv file itself, but this might work for you, give it a try, replace:
file_read = csv.reader(self.file)
with:
file_read = csv.reader(self.file, dialect=csv.excel_tab)
Or, open a file with universal newline mode and pass it to csv.reader, like:
reader = csv.reader(open(self.file, 'rU'), dialec...