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How to concatenate columns in a Postgres SELECT?
...catenated to NULL is NULL. If NULL values can be involved and the result shall not be NULL, use concat_ws() to concatenate any number of values (Postgres 9.1 or later):
SELECT concat_ws(', ', a, b) AS ab FROM foo;
Or concat() if you don't need separators:
SELECT concat(a, b) AS ab FROM foo;
No...
Why does the JVM still not support tail-call optimization?
Two years after does-the-jvm-prevent-tail-call-optimizations , there seems to be a prototype implementation and MLVM has listed the feature as "proto 80%" for some time now.
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CreateProcess error=206, The filename or extension is too long when running main() method
...Use directories instead of jar files
Use a packed jar files which contains all other jars, use the classpath variable inside the manifest file to point to the other jars
Use a special class loader which reads the classpath from a config file
Try to use one of the attached patches in the bug report d...
How to check if APK is signed or “debug build”?
... java.security.cert.CertificateException and android.content.pm.Signature. All other classes don't present multiple matches for me
– Christian García
Nov 29 '12 at 13:55
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Why does isNaN(“ ”) (string with spaces) equal false?
...
You should try NaN===NaN or NaN==NaN;-) I don't know if all this means the javascript engine is wacky or that javascript is bad for wacky programmers though.
– KooiInc
May 5 '09 at 22:01
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How do you hide the Address bar in Google Chrome for Chrome Apps?
...google.com
Linux:
google-chrome --app=https://google.com
This removes all toolbars, not just the address bar, but it will definitely increase your real estate without having to use Kiosk mode.
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How to enable MySQL Query Log?
...able, disable and to see the logs on live servers without restarting.
Log all queries in mysql
Here is a summary:
If you don't want or cannot restart the MySQL server you can proceed like this on your running server:
Create your log tables (see answer)
Enable Query logging on the database
(No...
Why a function checking if a string is empty always returns true? [closed]
...
Simple problem actually. Change:
if (strTemp != '')
to
if ($strTemp != '')
Arguably you may also want to change it to:
if ($strTemp !== '')
since != '' will return true if you pass is numeric 0 and a few other cases due to PHP's autom...
How can I get the timezone name in JavaScript?
...ationalization API supports getting the user timezone, and is supported in all current browsers.
console.log(Intl.DateTimeFormat().resolvedOptions().timeZone)
Keep in mind that on some older browser versions that support the Internationalization API, the timeZone property is set to undef...
Replacing a char at a given index in string? [duplicate]
...es what I need. I suppose the CPU cost is high, but the string sizes are small so it's all ok
7 Answers
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