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How do I force Postgres to use a particular index?
...ght be a good query plan today probably won't be a good query plan for all time, and index hints force a particular query plan for all time.
As a very blunt hammer, useful for testing, you can use the enable_seqscan and enable_indexscan parameters. See:
Examining index usage
enable_ parameters
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RSpec vs Cucumber (RSpec stories) [closed]
...ork with a non-technical member of a project who would want to waste their time reading tests. I dunno, maybe I'm lucky...
– Graham Ashton
Jul 23 '12 at 15:28
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Waiting until two async blocks are executed before starting another block
...TY_HIGH, 0), ^ {
// block1
NSLog(@"Block1");
[NSThread sleepForTimeInterval:5.0];
NSLog(@"Block1 End");
});
dispatch_group_async(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^ {
// block2
NSLog(@"Block2");
[NSThread sleepForTimeInterval:8.0];
NS...
How can I measure the actual memory usage of an application or process?
...snapshots of a program's heap. It produces a graph showing heap usage over time, including information about which parts of the program are responsible for the most memory allocations. The graph is supplemented by a text or HTML file that includes more information for determining where the most memo...
Automating the InvokeRequired code pattern
...formance hit using this approach, which could pile up when called multiple times. stackoverflow.com/a/747218/724944
– surfen
Nov 29 '11 at 12:05
5
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Flex-box: Align last row to grid
...ne, like Samsung Internet 6.0) because the spec was a bit ambiguous at the time. Now the spec has been clarified and the new versions of Chrome render auto-fit correctly, but browsers with old engine are still in use, so please be careful with this value.
– Ilya Streltsyn
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What is the difference between require() and library()?
... use library(), because this will give an error message at package loading time if the package is not available. require() will just fail without an error if the package is not there. This is the best time to find out if the package needs to be installed (or perhaps doesn't even exist because it it ...
How to drop column with constraint?
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Thank you so much - you saved me a lot of time. I have linked the question I asked to here
– Akash Yellappa
Jun 20 '19 at 17:48
add a comment
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Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...an application tier in front of the database, it can be converted "just-in-time" using a CASE expression e.g.
SELECT
a.answer_body,
CASE a.is_accepted WHEN 1 THEN 'TRUE' ELSE 'FALSE' END AS is_accepted
FROM answers AS a;
Storing boolean values as a character data type like char(1) or varc...
Cleaner way to do a null check in C#? [duplicate]
...e than simply rewriting a null check.
That said, I think that there are times where following the Law of Demeter is inappropriate. (It is, after all, a heuristic, not a hard-and-fast rule, even though it's called a "law.")
In particular, I think that if:
You have some classes that represent re...