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MySQL, update multiple tables with one query
...'blah';
To see what this is going to update, you can convert this into a select statement, e.g.:
SELECT t2.t1_id, t2.t3_id, t1.a, t2.b, t2.c AS t2_c, t3.c AS t3_c
FROM t1
INNER JOIN t2 ON t2.t1_id = t1.id
INNER JOIN t3 ON t2.t3_id = t3.id
WHERE t1.a = 'blah';
An example using the same tables as...
Removing all empty elements from a hash / YAML?
...mplementation is not recursive. As a curiosity, they implemented it using #select instead of #delete_if for performance reasons. See here for the benchmark.
In case you want to backport it to your Rails 3 app:
# config/initializers/rails4_backports.rb
class Hash
# as implemented in Rails 4
# ...
How does `is_base_of` work?
...;B, D>&)
D* (Host<B, D>&)
This would mean that we can't select by constness anymore. In an ordinary overload resolution scenario, the call would now be ambiguous because normally the return type won't participate in overload resolution. For conversion functions, however, there is ...
How to delete projects in IntelliJ 12?
...n a file menu appears, you can right click the unwanted project folder and select Delete.
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Convert seconds to Hour:Minute:Second
...ed to that of the TIME data type, which is from -838:59:59 to 838:59:59 :
SELECT SEC_TO_TIME(8525);
# 02:22:05
See: SEC_TO_TIME
Run the Demo
PostgreSQL example:
SELECT TO_CHAR('8525 second'::interval, 'HH24:MI:SS');
# 02:22:05
Run the Demo
...
Android Studio suddenly cannot resolve symbols
...
1.) Choose File option from menu on left top side of android studio.
2.) Select the option : "Invalidate Cache/ Restart.." It will open an dialog.
3.) Click on the first button with option : "Invalidate and Restart"
4.) It will close the studio and restart it. Start indexing of the project.
It...
“File not found” when running new LibGDX project
...s using Android Studio or IntelliJ IDEA, you need to follow these steps:
Select Run -> Edit Configurations from the menu
In the "Working Directory:" text box, append "/android/assets" to the path.
Note that if you execute tasks with gradle, this is not an issue. The gradle.build files are con...
Cannot use identity column key generation with ( TABLE_PER_CLASS )
...refer using 'TABLE' id generation strategy as it triggers lots of queries (select, insert, and update) and maintains locks to generate unique values for primary key. So what would be an alternate solution to this If we have a kinda big Inheritance scenario? It will certainly impact the performance a...
Why does jQuery or a DOM method such as getElementById not find the element?
...for document.getElementById , $("#id") or any other DOM method / jQuery selector not finding the elements?
9 Answers
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How to make EditText not editable through XML in Android?
...r example, the default editText is said to be single line. But you have to select an inputType for it to be single line. And if you select "none", it is still multiline.