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Why does Oracle 9i treat an empty string as NULL?
... spot on. The most confusing situations arise when '' is being implicitely converted to a VARCHAR2, such as cast('' as char(1)) is null which is... surprisingly TRUE
– sehe
Jul 19 '13 at 15:17
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How to compare two Dates without the time portion?
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I don't think that would work, even if converting to Strings was a good idea. The == operator doesn't necessarily return true for equivalent Strings (use equals()). You certainly can't use the other comparison operators you mentioned, either.
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Set time to 00:00:00
...Use *java.time* instead.
.toInstant() // Convert this moment in UTC from the legacy class `Date` to the modern class `Instant`.
.atZone( ZoneId.of( "Africa/Tunis" ) ) // Adjust from UTC to the wall-clock time used by the people of a particular region (a time...
Check time difference in Javascript
...diff = date2 - date1;
// 28800000 milliseconds (8 hours)
You can then convert milliseconds to hour, minute and seconds like this:
var msec = diff;
var hh = Math.floor(msec / 1000 / 60 / 60);
msec -= hh * 1000 * 60 * 60;
var mm = Math.floor(msec / 1000 / 60);
msec -= mm * 1000 * 60;
var ss = Ma...
How to delete items from a dictionary while iterating over it?
...t.keys() returns an iterator not a list.
As pointed out in comments simply convert mydict.keys() to a list by list(mydict.keys()) and it should work.
A simple test in the console shows you cannot modify a dictionary while iterating over it:
>>> mydict = {'one': 1, 'two': 2, 'three': 3...
Commit only part of a file in Git
...nted by lines beginning with "-". You can prevent staging their removal by converting the "-" to a " " (space).
modified content:
Modified content is represented by "-" lines (removing the old content) followed by "+" lines (adding the replacement content). You can prevent staging the modifica...
Boolean literals in PowerShell
...valent.
Note: Never expect that string literal true can get automatically converted to boolean. For example, if I run the below command:
installmyapp.ps1 -cleanuprequired true
it fails to execute the script with the below error:
Cannot process argument transformation on parameter 'cleanupreq...
SQL Server IN vs. EXISTS Performance
...an overall large result set).
I believe the optimizer is smart enough to convert between "in" vs "exists" when there is a significant cost difference due to (1) and (2), otherwise it may just be used as a hint (e.g. exists to encourage use of an a seekable index on the right side).
Both forms c...
How can I remove a pytz timezone from a datetime object?
...you are using a library like arrow, then you can remove timezone by simply converting an arrow object to to a datetime object, then doing the same thing as the example above.
# <Arrow [2014-10-09T10:56:09.347444-07:00]>
arrowObj = arrow.get('2014-10-09T10:56:09.347444-07:00')
# datetime.date...
How can I get Git to follow symlinks?
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$ git add src/main/path/ConvertSymlinkToDir fatal: 'src/main/path/ConvertSymlinkToDir' is beyond a symbolic link
– user1767316
Jul 21 '17 at 14:04
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