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What's wrong with using == to compare floats in Java?
...lse ensure that no float which compares unequal to itself gets stored in a table. Otherwise, a program which tries to e.g. count how many unique results can be produced from an expression when fed various inputs may regard every NaN value as unique.
– supercat
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How to delete from select in MySQL?
... clause.
Additionally, as shown in this answer you cannot modify the same table from a subquery within the same query. However, you can either SELECT then DELETE in separate queries, or nest another subquery and alias the inner subquery result (looks rather hacky, though):
DELETE FROM posts WHERE ...
Switch on Enum in Java [duplicate]
...r speed, the switch statement approach might be faster because it's just a table lookup in the bytecode. With your approach, you have to push a new function onto the stack. It's a micro-optimization, but if speed is super important it's something to keep in mind.
– DIMMSum
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Index (zero based) must be greater than or equal to zero
...Code:
string name="my name";
string age=25;
String.Format(@"Select * from table where name='{1}' and age={1}" +name, age);
//Right Code:
string name="my name";
string age=25;
String.Format(@"Select * from table where name='{1}' and age={1}" , name, age);
...
SQL multiple column ordering
... @NickBenes ...or you could say: it sorts by column2 and then performs STABLE sorting by column1. This is more clear for people that knows what stable sorting is.
– Atom
Oct 3 '16 at 13:49
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Only one expression can be specified in the select list when the subquery is not introduced with EXI
...r side of the IN. So the query needs to be of the form:
SELECT * From ThisTable WHERE ThisColumn IN (SELECT ThatColumn FROM ThatTable)
You also want to add sorting so you can select just from the top rows, but you don't need to return the COUNT as a column in order to do your sort; sorting in the...
Why is std::map implemented as a red-black tree?
...d red black probably only remains for historical reasons.
Why not a hash table?
A type only requires < operator (comparison) to be used as a key in a tree. However, hash tables require that each key type has a hash function defined. Keeping type requirements to a minimum is very important for ...
ng-repeat finish event
I want to call some jQuery function targeting div with table. That table is populated with ng-repeat .
15 Answers
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Still Reachable Leak detected by Valgrind
... reachable" memory can be considered a memory leak: assume you have a hash table where you add pointers to heap allocated memory as value. If you keep inserting new entries on the table, but won't remove and free those you don't need anymore, it can grow indefinitely, leaking heap memory event if th...
LINQ Join with Multiple Conditions in On Clause
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This works fine for 2 tables. I have 3 tables and on clause has to link 2 conditions from 3 tables.
My code:
from p in _dbContext.Products
join pv in _dbContext.ProductVariants on p.ProduktId equals pv.ProduktId
join jpr in leftJoinQuery
on new {...