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Can I implement an autonomous `self` member type in C++?
...question, not the answer. In many cases in software development (and especially maintenance) it is helpful to avoid redundancies in the code, so that changing something in one place does not require you to change code in another place. That's the whole point of auto and decltype or in this case of s...
How do I force Postgres to use a particular index?
How do I force Postgres to use an index when it would otherwise insist on doing a sequential scan?
6 Answers
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PHP json_encode encoding numbers as strings
...e of the json_encode() function is a string. Regarding the MySQL returning all fields as strings, yes I have also encountered this specifically with PDO. The way I see it you should always cast values you expect to be numeric to integer (or float) in PHP to make sure, do not trust MySQL or any other...
Left Align Cells in UICollectionView
... use.
CGFloat maxY = -1.0f;
//this loop assumes attributes are in IndexPath order
for (UICollectionViewLayoutAttributes *attribute in attributes) {
if (attribute.frame.origin.y >= maxY) {
leftMargin = self.sectionInset.left;
}
attribute.frame = CG...
How do you produce a .d.ts “typings” definition file from an existing JavaScript library?
... foreach { tsc $_.Name }
Finally, combine all the *.d.ts files into one index.d.ts, removing the import statements and removing the default from each export statement.
Remove-Item index.d.ts;
Get-ChildItem -Path *.d.ts -Exclude "Index.d.ts" | `
foreach { Get-Content $_ } | `
where { !$_.To...
Asynchronous shell exec in PHP
...e got a PHP script that needs to invoke a shell script but doesn't care at all about the output. The shell script makes a number of SOAP calls and is slow to complete, so I don't want to slow down the PHP request while it waits for a reply. In fact, the PHP request should be able to exit without ter...
Does order of where clauses matter in SQL?
...PLE having 3 columns ID, LastName, FirstName , none of these columns are indexed.
LastName is more unique, and FirstName is less unique.
...
Rails: fields_for with index?
...method (or way to pull off similar functionality) to do a fields_for_with_index ?
9 Answers
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efficient circular buffer?
...nderstandable when the deque can grow to infinity, but if maxlen is given, indexing an element should be constant time.
– lvella
Nov 13 '15 at 21:57
1
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postgresql list and order tables by size
...al_relation_size(<relation_name>) - gets total size of table and its index in bytes.
pg_relation_size(<relation_name>) - gets relation (table/index) size in bytes.
pg_index_size(<relation_name>) - gets index size of the relation in bytes.
current_database() - gets the currently ...