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What is the difference between JOIN and UNION?
...ed when columns from one table match columns from another. This match is called the join condition.
This makes joins really great for looking up values and including them in results. This is usually the result of denormalizing (reversing normalization) and involves using the foreign key in one ta...
List submodules in a Git repository
...t repository that has several submodules in it. How do I list the names of all the submodules after git submodule init has been run?
...
Preserve line breaks in angularjs
... up wouldn't be pre-line the preferred one? It's closer to the way HTML usually renders the the text contents of its nodes and still preservers the newlines.
– aaki
Jan 27 '15 at 18:19
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Showing line numbers in IPython/Jupyter Notebooks
...l line numbers. In more recent notebook versions Shift-L should toggle for all cells.
If you can't remember the shortcut, bring up the command palette Ctrl-Shift+P (Cmd+Shift+P on Mac), and search for "line numbers"), it should allow to toggle and show you the shortcut.
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Ignoring time zones altogether in Rails and PostgreSQL
...time zone.
timestamptz is the preferred type in the date/time family, literally. It has typispreferred set in pg_type, which can be relevant:
Generating time series between two dates in PostgreSQL
Internal storage and epoch
Internally, timestamps occupy 8 bytes of storage on disk and in RAM. It is...
HTML select form with option to enter custom value
...e input, with a value of the id of the datalist.
Update: As of March 2019 all major browsers (now including Safari 12.1 and iOS Safari 12.3) support datalist to the level needed for this functionality. See caniuse for detailed browser support.
It looks like this:
<input type="text" list="c...
Array or List in Java. Which is faster?
I have to keep thousands of strings in memory to be accessed serially in Java. Should I store them in an array or should I use some kind of List ?
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How does the getView() method work when creating your own custom adapter?
...ided so you can inflate your view into that for proper layout parameters.
All these together can be used to effectively create the view that will appear in your list (or other view that takes an adapter):
public View getView(int position, @Nullable View convertView, ViewGroup parent){
if (conv...
NoSQL Use Case Scenarios or WHEN to use NoSQL [closed]
With all the hype it seems really hard to find reliable information on when to use this. So I pose the following questions, and I'm sorry if these are really dumb questions in advance:
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How do you remove the root CA certificate that fiddler installs
...ddler Options -> HTTPS. Then click the "Actions" button and then "Reset All Certificates"
It will popup a message that it could take a while but it's really quick. Approve all popups and there you go.
Pay attention not to re-approve the certificate again (when I did it the message for approving t...