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SQL SELECT speed int vs varchar
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Some rough benchmarks:
4 million records in Postgres 9.x
Table A = base table with some columns
Table B = Table A + extra column id of type bigint with random numbers
Table C = Table A + extra column id of type text with random 16-char ASCII strings
Results on 8GB RAM, i7, SSD laptop:
Siz...
How to use SCNetworkReachability in Swift
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Swift 3, IPv4, IPv6
Based on the Martin R's answer:
import SystemConfiguration
func isConnectedToNetwork() -> Bool {
guard let flags = getFlags() else { return false }
let isReachable = flags.contains(.reachable)
let needsConnec...
How to determine the content size of a UIWebView?
...ds rectangle. Subclasses can override this method to return a custom value based on the desired layout of any subviews. For example, a UISwitch object returns a fixed size value that represents the standard size of a switch view, and a UIImageView object returns the size of the image it is currently...
FormsAuthentication.SignOut() does not log the user out
...de caching in the Page_Load event of each page, or in the OnLoad() of your base page:
Response.Cache.SetCacheability(HttpCacheability.NoCache);
You might also like to call:
Response.Cache.SetNoStore();
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Convert from ASCII string encoded in Hex to plain ASCII?
...his, here's one of the shortest, using only python-provided stuff:
import base64
hex_data ='57696C6C20796F7520636F6E76657274207468697320484558205468696E6720696E746F20415343494920666F72206D653F2E202E202E202E506C656565656173652E2E2E212121'
ascii_string = str(base64.b16decode(hex_data))[2:-1]
print (a...
How to convert an array to object in PHP?
... (object) $array == nice KISS implementation !
– mate64
Dec 30 '11 at 16:52
16
Why would anyone w...
How to use CSS to surround a number with a circle?
...ed to tweak the size of the outer container so that it is the perfect size based on the font size and number of characters to be displayed. If you are mixing 1 digit numbers and 4 digit numbers, it won't work. If the ratio between the font size and the circle size isn't perfect, you'll either end up...
What is the maximum possible length of a .NET string?
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Based on my highly scientific and accurate experiment, it tops out on my machine well before 1,000,000,000 characters. (I'm still running the code below to get a better pinpoint).
UPDATE:
After a few hours, I've given up. Fi...
To ARC or not to ARC? What are the pros and cons? [closed]
...ing out of memory management practice when you have to switch between code-bases. Some of my projects run on 10.4, so I still do a lot of Objective-C 1.0 work (so no @synthesize, let alone ARC). But you get used to switching modes pretty well.
– Rob Napier
Jan ...
How is the undo tree used in Vim?
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Brian CarperBrian Carper
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