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Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes
...d="foo" value="#{bean.foo}" required="true" />
<p:message id="foo_m" for="foo" />
<p:inputText id="bar" value="#{bean.bar}" required="true" />
<p:message id="bar_m" for="bar" />
<p:commandButton action="#{bean.action}" update="@form" />
</h:form>
(no...
mysql error 1364 Field doesn't have a default values
...
Set a default value for Created_By (eg: empty VARCHAR) and the trigger will update the value anyways.
create table try (
name varchar(8),
CREATED_BY varchar(40) DEFAULT '' not null
);
...
psql: FATAL: role “postgres” does not exist
... which will just use the latest version.
start postgres server manually: pg_ctl -D /usr/local/var/postgres start
To start server at startup
mkdir -p ~/Library/LaunchAgents
ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.post...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...z = {**x, **y}
In Python 2, (or 3.4 or lower) write a function:
def merge_two_dicts(x, y):
z = x.copy() # start with x's keys and values
z.update(y) # modifies z with y's keys and values & returns None
return z
and now:
z = merge_two_dicts(x, y)
In Python 3.9.0a4 or greater...
How to add 'ON DELETE CASCADE' in ALTER TABLE statement
...t instead of modify constraint.
Now this is the command:
ALTER TABLE child_table_name
ADD CONSTRAINT fk_name
FOREIGN KEY (child_column_name)
REFERENCES parent_table_name(parent_column_name)
ON DELETE CASCADE;
s...
How to log something in Rails in an independent log file?
...t like the usual Rails logger:
class User < ActiveRecord::Base
def my_logger
@@my_logger ||= Logger.new("#{Rails.root}/log/my.log")
end
def before_save
my_logger.info("Creating user with name #{self.name}")
end
end
Here I used a class attribute to memoize the logger. This way ...
Optional Parameters in Go?
...amp;Foobar{}
// ... (write initializations with default values)...
for _, op := range options{
err := op(fb)
if err != nil {
return nil, err
}
}
return fb, nil
}
where each option is a function which mutates the Foobar. Then provide convenient ways for your user to use or...
How do I set up IntelliJ IDEA for Android applications?
...n a Mac, the Java JDK appears at /Library/Java/JavaVirtualMachines/jdk1.7.0_09.jdk
– emrys57
Nov 22 '12 at 14:13
1
...
Is there an easy way to add a border to the top and bottom of an Android View?
...move the solid if you don't want a fill. The set background="@drawable/your_shape_drawable" on your layout/view.
Option 2: Background View
Here's a little trick I've used in a RelativeLayout. Basically you have a black square under the view you want to give a border, and then give that view some p...
ADB not recognising Nexus 4 under Windows 7
...B driver via SDK Manager.exe. In order to get that to run I had to set JAVA_HOME to the location of my JDK.
– Ben Challenor
Feb 9 '13 at 12:14
3
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