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Database development mistakes made by application developers [closed]
...ng appropriate indices
This is a relatively easy one but still it happens all the time. Foreign keys should have indexes on them. If you're using a field in a WHERE you should (probably) have an index on it. Such indexes should often cover multiple columns based on the queries you need to execut...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the row won't actually be inserted if it results in a duplicate key. But the statement won't generate an error. It generates a warning instead. These cases include:
Inserting a duplicate key in columns with PRIMARY KEY or UNIQUE constrain...
How to find out element position in slice?
...
this does not find the original index; rather it loses all the indexes by re-ordering them
– newacct
Nov 29 '11 at 20:16
...
Chrome DevTools Devices does not detect device when plugged in
...s://developers.google.com/chrome-developer-tools/docs/remote-debugging
Install Windows USB driver http://developer.samsung.com/android/tools-sdks/Samsung-Android-USB-Driver-for-Windows
Install Android SDK http://developer.android.com/sdk/index.html
Install Android SDK Platform-tools http://developer...
What is the difference between an Azure Web Site and an Azure Web Role
...pps (formerly Web Sites):
Ability to run elevated startup scripts to install apps, modify registry settings, install performance counters, fine-tune IIS, etc.
Ability to split an app up into tiers (maybe Web Role for front end, Worker Role for backend processing) and scale independently
Ability to...
Convert HTML to PDF in .NET
...e wkhtmltopdf solutions on my project and had a bunch of hurdles.
I personally would avoid using wkhtmltopdf - based solutions on Hosted Enterprise applications for the following reasons.
First of all wkhtmltopdf is C++ implemented not C#, and you will
experience various problems embedding it wit...
Regular expression to match DNS hostname or IP Address?
...o be escaped with \.
ValidHostnameRegex is valid as per RFC 1123. Originally, RFC 952 specified that hostname segments could not start with a digit.
http://en.wikipedia.org/wiki/Hostname
The original specification of
hostnames in RFC
952,
mandated that labels could not start
with a d...
.net implementation of bcrypt
...han BCrypt.dll or it will conflict with the new Windows API in Vista that calls functions in a 'bcrypt.dll', so if you have Bcrypt.net as Bcrypt.dll in your web app bin/ directory Windows won't be able to find the correct dll and you will get some cryptic errors.
– thelsdj
...
What are the differences between vector and list data types in R?
...
Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
Can you help me understand this? “Common REST Mistakes: Sessions are irrelevant”
...ature of HTTP.
Okay, I get that HTTP authentication
is done automatically on every message
- but how?
Yes, the username and password is sent with every request. The common methods to do so are basic access authentication and digest access authentication. And yes, an eavesdropper can capt...