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Understanding Python's “is” operator
...ation for the is operator:
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object.
Use the == operator instead:
print(x == y)
This prints True. x and y are two separate lists:
x[0] = 4
print(y) # prints [1, 2, 3]
print(x == y) # p...
How do I concatenate strings and variables in PowerShell?
...
Write-Host "$($assoc.Id) - $($assoc.Name) - $($assoc.Owner)"
See the Windows PowerShell Language Specification Version 3.0, p34, sub-expressions expansion.
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Patterns for handling batch operations in REST web services?
...ource. For example, to delete several messages at once.
DELETE /mail?&id=0&id=1&id=2
It's a little more complicated to batch update partial resources, or resource attributes. That is, update each markedAsRead attribute. Basically, instead of treating the attribute as part of each reso...
PHP - Extracting a property from an array of objects
...5 or later, the best way is to use the built in function array_column():
$idCats = array_column($cats, 'id');
But the son has to be an array or converted to an array
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SQL select only rows with max value on a column [duplicate]
...All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common question in SQL: find the whole data for the row with some max value in a co...
Preventing Laravel adding multiple records to a pivot table
...condition like this one :
if (! $cart->items->contains($newItem->id)) {
$cart->items()->save($newItem);
}
Or/and you can add unicity condition in your database, it would throw an exception during an attempt of saving a doublet.
You should also take a look at the more straightf...
how to exclude null values in array_agg like in string_agg using postgres?
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SQL Fiddle
select
id,
(select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users,
(select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users
from (
...
SQL Joins Vs SQL Subqueries (Performance)?
...vary. The speed will depend a lot on indexes (do you have indexes on both ID columns? That will help a lot...) among other things.
The only REAL way to tell with 100% certainty which is faster is to turn on performance tracking (IO Statistics is especially useful) and run them both. Make sure to...
SQL variable to hold list of integers
...
Table variable
declare @listOfIDs table (id int);
insert @listOfIDs(id) values(1),(2),(3);
select *
from TabA
where TabA.ID in (select id from @listOfIDs)
or
declare @listOfIDs varchar(1000);
SET @listOfIDs = ',1,2,3,'; --in this solution need put...
How do I link to part of a page? (hash?)
...
If there is an <a name="foo"> tag or any tag with an id (e.g., <div id="foo">), then you can simply append #foo to the URL. Otherwise, you can't arbitrarily link to portions of a page.
Here's a complete example: <a href="http://example.com/page.html#foo">Jump to #...