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Objective-C: Where to remove observer for NSNotification?
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I'd turn the order of these instructions around... Using self after [super dealloc] makes me nervous... (even if the receiver is unlikely to actually dereference the pointer in any way, well, you never know, how they implemented NSNotific...
Remove Identity from a column in a table
... you want to do this without adding and populating a new column, without reordering the columns, and with almost no downtime because no data is changing on the table, let's do some magic with partitioning functionality (but since no partitions are used you don't need Enterprise edition):
Remove al...
View's SELECT contains a subquery in the FROM clause
...y client_id
create view view_credit_status as
select
credit_orders.client_id,
sum(credit_orders.number_of_credits) as purchased,
ifnull(t1.credits_used,0) as used
from credit_orders
left outer join view_clients_credit_usage as t1 on t1.client_id = credit_ord...
Getting an object from an NSSet
... to get a member (not random), or convert it to an array (in no particular order) with allObjects.
A set is appropriate when you don't want duplicates, don't care about order, and want fast membership testing.
share
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select * vs select column
...as to what you want, it will first need to check the table's definition in order to determine the columns on that table. That lookup will cost some time - not much in a single query - but it adds up over time
if you need only 2/3 of the columns, you're selecting 1/3 too much data which needs to be r...
Mac OS X - EnvironmentError: mysql_config not found
...ll mysqlclient if using python 3)
If you did all those steps in the same order, and you still got an error, read on to the end, if, however, you did not follow these exact steps try, following them from the very beginning.
So, you followed the steps, and you're still geting an error, well, there ...
The type must be a reference type in order to use it as parameter 'T' in the generic type or method
...koverflow.com%2fquestions%2f6451120%2fthe-type-must-be-a-reference-type-in-order-to-use-it-as-parameter-t-in-the-gen%23new-answer', 'question_page');
}
);
Post as a guest
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How to set iPhone UIView z index?
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UIView siblings are stacked in the order in which they are added to their superview. The UIView hierarchy methods and properties are there to manage view order. In UIView.h:
@property(nonatomic,readonly) UIView *superview;
@property(nonatomic,readonly,copy) N...
Set title background color
... one thing that this one is doing it from code so it is little delayed. In order to avoid such situation I will have to write every thing in the xml and nothing in the code. so can you please guide me in that?
– Shaista Naaz
Apr 29 '11 at 12:39
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How does setting baselineAligned to false improve performance in LinearLayout?
...="false" , you're preventing the extra work your app's layout has to do in order to Align its children's baselines; which can obviously increase the performance. (Fewer unnecessary operations on UI => Better performance)
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