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Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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How do you copy a record in a SQL table but swap out the unique id of the new row?
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Any fields not specified should receive their default value (which is usually NULL when not defined).
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Ignore .pyc files in git repository
...t to to do it beforehand, if you just add the line to the .gitignore file, all previously committed .pyc files will still be tracked, so you'll need to remove them from the repository.
If you are on a Linux system (or "parents&sons" like a MacOSX), you can quickly do it with just this one line ...
Exact difference between CharSequence and String in java [duplicate]
...h can be modified
Any method which accepts a CharSequence can operate on all of these equally well. Any method which only accepts a String will require conversion. So using CharSequence as an argument type in all the places where you don't care about the internals is prudent. However you should us...
How can I get clickable hyperlinks in AlertDialog from a string resource?
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Then, I'm getting error Calling startActivity() from outside of an Activity context requires the FLAG_ACTIVITY_NEW_TASK flag. Is this really what you want?
– ViliusK
Dec 8 '16 at 13:08
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How to structure a express.js application?
... it.
Of those, I think Twitter's matador is structured pretty well. We actually used a very similar approach to how they load up parts of the app.
derby.js also looks extremely interesting. It's akin to meteor without all of the hype and actually gives credit where credit is due (notably, node and e...
How do I force Postgres to use a particular index?
...of why and what you can do instead can be found here. The reasons are basically that it's a performance hack that tends to cause more problems later down the line as your data changes, whereas PostgreSQL's optimizer can re-evaluate the plan based on the statistics. In other words, what might be a go...
What's to stop malicious code from spoofing the “Origin” header to exploit CORS?
...header Origin: http://foo.com , and bar must respond with Access-Control-Allow-Origin: http://foo.com .
3 Answers
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XmlSerializer: remove unnecessary xsi and xsd namespaces
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Since Dave asked for me to repeat my answer to Omitting all xsi and xsd namespaces when serializing an object in .NET, I have updated this post and repeated my answer here from the afore-mentioned link. The example used in this answer is the same example used for the other questio...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...ead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 cannot store
the character at all, you do not have any supplementary characters in
utf8 columns and you need not worry about converting characters or
losi...