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Objective-C class -> string like: [NSArray className] -> @“NSArray”
...c. NSStringFromClass just pulls the name of the class from this struct and converts it to an NSString. Don't store the class name in a static NSString, it won't offer any performance advantage.
– dreamlax
Apr 10 '11 at 23:43
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Query for array elements inside JSON type
...src":"bar.png"}]
, "background":"background.png"}'::json)
)
SELECT *
FROM reports r, json_array_elements(r.data#>'{objects}') obj
WHERE obj->>'src' = 'foo.png';
The CTE (WITH query) just substitutes for a table reports.
Or, equivalent for just a single level of nesting:
SE...
Build unsigned APK file with Android Studio
...nu in the toolbar at the top (Open 'Edit Run/Debug configurations' dialog)
Select "Edit Configurations"
Click the "+"
Select "Gradle"
Choose your module as a Gradle project
In Tasks: enter assemble
Press Run
Your unsigned APK is now located in
ProjectName\app\build\outputs\apk
For detailed inf...
How to show math equations in general github's markdown(not github's blog)
...
this worked great. I had to convert a jupyter notebook (.ipynb) to .md and the equations were essentially multiline latex code.
– Marc Maxmeister
Jun 17 '19 at 18:21
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SQL left join vs multiple tables on FROM line?
...nts that have employees, but always list all companies.
So you do this:
SELECT * -- for simplicity
FROM Company, Department, Employee
WHERE Company.ID *= Department.CompanyID
AND Department.ID = Employee.DepartmentID
Note that the last one there is an inner join, in order to fulfill the crite...
Descending order by date filter in AngularJs
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In my case, the orderBy is determined by a select box. I prefer Ludwig's response because you can set the sort direction in the select options as such:
$scope.options = [
{ label: 'Title', value: 'title' },
{ label: 'Newest', value: '...
Python loop counter in a for loop [duplicate]
...
Use enumerate() like so:
def draw_menu(options, selected_index):
for counter, option in enumerate(options):
if counter == selected_index:
print " [*] %s" % option
else:
print " [ ] %s" % option
options = ['Option 0', 'Option...
How do you do block comments in YAML?
...rt about it, but if you use Sublime Text for your editor, the steps are:
Select the block
cmd+/ on Mac or ctrl+/ on Linux & Windows
Profit
I'd imagine that other editors have similar functionality too. Which one are you using? I'd be happy to do some digging.
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Should I use char** argv or char* argv[]?
...It will behave as a pointer, because as explained earlier an array will be converted to a pointer when its value is read. But it should not be confused with pointers.
One classic example is the following:
char c[10];
char **c = &c; // does not work.
typedef char array[10];
array *pc = &...
What GRANT USAGE ON SCHEMA exactly do?
...a schema doesn't grant rights on the tables within.
If you have rights to SELECT from a table, but not the right to see it in the schema that contains it then you can't access the table.
The rights tests are done in order:
Do you have `USAGE` on the schema?
No: Reject access.
Yes: Do...