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What is the Oracle equivalent of SQL Server's IsNull() function?
In SQL Server we can type IsNull() to determine if a field is null. Is there an equivalent function in PL/SQL?
4 Answers...
What is the difference between “screen” and “only screen” in media queries?
What is the difference between screen and only screen in media queries?
5 Answers
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Using Python's os.path, how do I go up one directory?
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Using abspath will just clean it up a bit. If it's not there, the actual string for the path name will be /Users/hobbes3/Sites/mysite/mysite/../templates, which is perfectly fine, but just a little more cluttered. It also ensures that Django's reminder to use absolute...
How to create and write to a txt file using VBA
I have a file which is manually added or modified based on the inputs. Since most of the contents are repetitive in that file, only the hex values are changing, I want to make it a tool generated file.
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Java: function for arrays like PHP's join()?
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If you were looking for what to use in android, it is:
String android.text.TextUtils.join(CharSequence delimiter, Object[] tokens)
for example:
String joined = TextUtils.join(";", MyStringArray);
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Database Design for Revisions?
...sorts of other problems.
Design 2 does have problems with schema changes. If you change the Employees table you have to change the EmployeeHistories table and all the related sprocs that go with it. Potentially doubles you schema change effort.
Design 1 works well and if done properly does not cos...
Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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If you want to let PostgreSQL generate the index name, use ALTER TABLE tablename ADD UNIQUE (columns);. (Note that the CONSTRAINT keyword must be omitted.)
– jpmc26
Nov 26 '14 at 1:41
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mongo group query how to keep fields
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If you want to keep the information about the first matching entries for each group, you can try aggregating like:
db.test.aggregate({
$group: {
_id : '$name',
name : { $first: '$name' },
age : { $first: '$age' },...
Are database triggers evil? [closed]
... @HGLEM, agree there should be a specialist to work out triggers. Real life scenario - there isn't. Real life scenario - days spent trying to identify a bug related to a forgotten trigger. Real life scenario - trigger logic is being desperately pushed out into application logic where it can be ea...
Concatenate a vector of strings/character
If I have a vector of type character, how can I concatenate the values into string? Here's how I would do it with paste() :
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