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In which case do you use the JPA @JoinTable annotation?
... project_id
name name task_id
The Project_Tasks table is called a "Join Table". To implement this second solution in JPA you need to use the @JoinTable annotation. For example, in order to implement a uni-directional one-to-many association, we can define our entities as such:
Proj...
How do I base64 encode (decode) in C?
... *output_length = 4 * ((input_length + 2) / 3);
char *encoded_data = malloc(*output_length);
if (encoded_data == NULL) return NULL;
for (int i = 0, j = 0; i < input_length;) {
uint32_t octet_a = i < input_length ? (unsigned char)data[i++] : 0;
uint32_t octet_b = ...
How to force link from iframe to be opened in the parent window
...of the page in the iframe:
<base target="_parent">
This will load all links on the page in the parent window. If you want your links to load in a new window, use:
<base target="_blank">
This tag is fully supported in all browsers.
...
Programmatically open new pages on Tabs
...cript you can use
window.open('page.html','_newtab');
Said that, I partially agree with Sam. You shouldn't force user to open new pages or new tab without showing them a hint on what is going to happen before they click on the link.
Let me know if it works on other browser too (I don't have a ch...
Can I use __init__.py to define global variables?
I want to define a constant that should be available in all of the submodules of a package. I've thought that the best place would be in in the __init__.py file of the root package. But I don't know how to do this. Suppose I have a few subpackages and each with several modules. How can I access th...
Python - Create a list with initial capacity
...bject %d" % ( i, )
result.append(message)
return result
def doAllocate( size=10000 ):
result=size*[None]
for i in range(size):
message= "some unique object %d" % ( i, )
result[i]= message
return result
Results. (evaluate each function 144 times and average ...
Why would you use an ivar?
I usually see this question asked the other way, such as Must every ivar be a property? (and I like bbum's answer to this Q).
...
How to convert JSON data into a Python object
...ry, the order of items will directly correspond.". Good to know for such small, local code blocks. I'd add a comment though to explicitly alert maintainers of code of such a dependency.
– cfi
Jun 1 '16 at 7:33
...
How to implement a good __hash__ function in python [duplicate]
... are equal. It also shouldn't change over the lifetime of the object; generally you only implement it for immutable objects.
A trivial implementation would be to just return 0. This is always correct, but performs badly.
Your solution, returning the hash of a tuple of properties, is good. But note...
Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
...