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Where does Oracle SQL Developer store connections?
...my connection info with what is set up in the SQL Explorer's file. I found all the *.ora files and renamed them to see if I could find what file (through the process of elimination) the connections were stored in, but I wasn't successful. Any help would be appreciated.
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E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
What happens if you static_cast invalid value to enum class?
...ue is specified(*), and no Undefined Behaviour (UB) is involved. More generally, as you cast from the underlying type to the enumeration type, no value in data[0] can lead to UB for the static_cast.
After CWG 1766 (C++17)
See CWG defect 1766.
The [expr.static.cast]p10 paragraph has been strengthene...
How do I write JSON data to a file?
... codecs.getwriter('utf-8')(f), ensure_ascii=False)
The codecs.getwriter call is redundant in Python 3 but required for Python 2
Readability and size:
The use of ensure_ascii=False gives better readability and smaller size:
>>> json.dumps({'price': '€10'})
'{"price": "\\u20ac10"}'
&...
How to use java.net.URLConnection to fire and handle HTTP requests?
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First a disclaimer beforehand: the posted code snippets are all basic examples. You'll need to handle trivial IOExceptions and RuntimeExceptions like NullPointerException, ArrayIndexOutOfBoundsException and consorts yourself.
Preparing
We first need to know at least the URL and the c...
Fastest way to copy file in node.js
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I used this method and all I got was a blank file on write. any ideas why? fs.createReadStream('./init/xxx.json').pipe(fs.createWriteStream('xxx.json'));
– Timmerz
Aug 20 '14 at 15:23
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How do I add a new sourceset to Gradle?
...nk it up? I also find this exact situation severely lacking in docs: It is all well and good defining a new sourceSet, but no info about "hooking this into" the actual compile, jar, test and whatnot targets - as this example does (except for adding into the jar, or making a new jar, out of that sour...
How to call Android contacts list?
I'm making an Android app, and need to call the phone's contact list. I need to call the contacts list function, pick a contact, then return to my app with the contact's name. Here's the code I got on the internet, but it doesnt work.
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Is it possible to Turn page programmatically in UIPageViewController?
Is it possible to turn page programmatically in UIPageViewController ?
17 Answers
17
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PostgreSQL create table if not exists
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CREATE TABLE myschema.mytable (i integer);
END IF;
END
$func$;
Call:
SELECT create_mytable(); -- call as many times as you want.
Notes:
The columns schemaname and tablename in pg_tables are case-sensitive. If you double-quote identifiers in the CREATE TABLE statement, you need ...