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SQLite table constraint - unique on multiple columns
...t leaves off the UNIQUE constraint. I was only able to do this by using an index.
– gattsbr
Aug 11 at 14:55
...
What's the difference between echo, print, and print_r in PHP?
..._3=array(99,98,97) // Arrays are not possible with echo (loop or index value required)
$var_4=array("P"=>"3","J"=>"4"); // Arrays are not possible with echo (loop or index value required)
You can also use echo statement with or without parenthese
echo ("Hello World"); // thi...
How to make an immutable object in Python?
...ter(1))
p = Point(2, 3)
p.x
# 2
p.y
# 3
Edit: If you want to get rid of indexing either, you can override __getitem__():
class Point(tuple):
__slots__ = []
def __new__(cls, x, y):
return tuple.__new__(cls, (x, y))
@property
def x(self):
return tuple.__getitem__(se...
What does 'COLLATE SQL_Latin1_General_CP1_CI_AS' do?
... such as object names (i.e. sys.objects), column names (i.e. sys.columns), index names (i.e. sys.indexes), etc.
The Collation used for Database-level objects: tables, columns, indexes, etc.
Also:
ASCII is an encoding which is 8-bit (for common usage; technically "ASCII" is 7-bit with character v...
Escaping a forward slash in a regular expression
My question is a simple one, and it is about regular expression escaping. Do you have to escape a forward slash / in a regular expression? And how would you go about doing it?
...
How to wait for a keypress in R?
...ture to it? press esc keep to exit loop ?
– I_m_LeMarque
Mar 21 '18 at 18:59
4
@nnn this does not...
Android Studio: Javadoc is empty on hover
...t.
Even after resizing it though, I still see it return to it's tiny size quite often... I'm glad I have my docs back, even if it does mean dealing with this annoyance.
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How to tell if node.js is installed or not
...ory using mkdir NodeJs. Inside the NodeJs folder create a file using touch index.js. Open your index.js either using vi or in your favourite text editor. Type in console.log('Welcome to NodesJs.') and save it. Navigate back to your saved file and type node index.js. If you see Welcome to NodesJs. yo...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...aka the COLLATE cast approach, can lead to potential bottleneck, cause any index defined on the column will not be used causing a full scan.
Even though I did not try out Option 3, my hunch is that it will suffer the same consequences of option 1 and 2.
Lastly, Option 4 is the best option for very...
Select objects based on value of variable in object using jq
...
Adapted from this post on Processing JSON with jq, you can use the select(bool) like this:
$ jq '.[] | select(.location=="Stockholm")' json
{
"location": "Stockholm",
"name": "Walt"
}
{
"location": "Stockholm",
"name": "Donald"
}
...