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How do I add a foreign key to an existing SQLite table?
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You can't.
Although the SQL-92 syntax to add a foreign key to your table would be as follows:
ALTER TABLE child ADD CONSTRAINT fk_child_parent
FOREIGN KEY (parent_id)
REFERENCES parent(id);
SQLite doesn't support the ADD CONST...
Firing events on CSS class changes in jQuery
How can I fire an event if a CSS class is added or changed using jQuery?
Does changing of a CSS class fire the jQuery change() event?
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MySQL - Rows to Columns
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I'm going to add a somewhat longer and more detailed explanation of the steps to take to solve this problem. I apologize if it's too long.
I'll start out with the base you've given and use it to define a couple of terms that I'll use ...
How can I add new keys to a dictionary?
Is it possible to add a key to a Python dictionary after it has been created?
16 Answers
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How to avoid null checking in Java?
... contracts they are participating in and defensively overcheck for nulls. Additionally, when writing their own code, they tend to rely on returning nulls to indicate something thus requiring the caller to check for nulls.
To put this another way, there are two instances where null checking comes u...
MSBuild doesn't copy references (DLL files) if using project dependencies in solution
...ich will result in assembly B being copied to project Y's bin directory:
Add a reference to assembly B in project Y.
Add dummy code to a file in project X that uses assembly B.
Personally I prefer option 2 for a couple reasons.
If you add another project in the future that references project X...
Programmatically go back to the previous fragment in the backstack
Say I have an activity that has fragments added programmatically:
12 Answers
12
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Javascript event handler with parameters
...to do, but you can make variables available in any event handler using the advantages of function closures:
function addClickHandler(elem, arg1, arg2) {
elem.addEventListener('click', function(e) {
// in the event handler function here, you can directly refer
// to arg1 and arg2...
Writing string to a file on a new line every time
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James MV
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answered May 27 '10 at 3:59
halfdanhalfdan
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Are the PUT, DELETE, HEAD, etc methods available in most web browsers?
...submitted form's data to be processed, which may
result in an item being added to a database, the creation of a new web
page resource, the updating of the existing page, or all of the
mentioned outcomes.
The keyword dialog, mapping to the state dialog, indicating that
submitting the for...