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Check if a table exists in Rails
...? 'kittens'
In Rails 2, 3 & 4 the API is about tables.
# Listing of all tables and views
ActiveRecord::Base.connection.tables
# Checks for existence of kittens table/view (Kitten model)
ActiveRecord::Base.connection.table_exists? 'kittens'
Getting the status of migrations:
# Tells you all...
How do I check if a given string is a legal/valid file name under Windows?
...than ASCII space)
Any other character that the target file system does not allow (say, trailing periods or spaces)
Any of the DOS names: CON, PRN, AUX, NUL, COM0, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT0, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9 (and avoid AUX.txt, etc)...
How to create directory automatically on SD card
...ollowing location
FileOutputStream fos = new FileOutputStream("/sdcard/Wallpaper/"+fileName);
but I'm getting the exception java.io.FileNotFoundException
However, when I put the path as "/sdcard/" it works.
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What is a Windows Handle?
...ing) a handle is an abstraction which hides a real memory address from the API user, allowing the system to reorganize physical memory transparently to the program. Resolving a handle into a pointer locks the memory, and releasing the handle invalidates the pointer. In this case think of it as an ...
Why shouldn't all functions be async by default?
...kind words. It is indeed an awesome feature and I am glad to have been a small part of it.
If all my code is slowly turning async, why not just make it all async by default?
Well, you're exaggerating; all your code isn't turning async. When you add two "plain" integers together, you're not awa...
jQuery: more than one handler for same event
...
Both handlers will run, the jQuery event model allows multiple handlers on one element, therefore a later handler does not override an older handler.
The handlers will execute in the order in which they were bound.
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How do I show multiple recaptchas on a single page?
...ave 2 forms on a single page. One of the forms has a recaptcha displaying all the time. The other should display a recaptcha only after a certain event such as maxing out login attempts. So there are times when I would need 2 recaptchas to appear on the same page. Is this possible? I know I cou...
How to Set Opacity (Alpha) for View in Android
...ton (or any other view) in your xml:
android:color="#66FF0000" // Partially transparent red
In the above example, the color would be a partially transparent red.
When defining the color of a view, the format can be either #RRGGBB or #AARRGGBB, where AA is the hex alpha value. FF would be full...
Java and SQLite [closed]
... which uses embedded native SQLite libraries on Windows, Linux, OS X, and falls back to pure Java implementation on other OSes: https://github.com/xerial/sqlite-jdbc (formerly zentus)
Another Java - SWIG wrapper. It only works on Win32. http://rodolfo_3.tripod.com/index.html
sqlite-java-shell: 100% ...
Display / print all rows of a tibble (tbl_df)
...ame manipulation package in R. It prevents long table outputs when accidentally calling the data frame.
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