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Improve INSERT-per-second performance of SQLite
...more memory will be used for your database.
If you have indices, consider calling CREATE INDEX after doing all your inserts. This is significantly faster than creating the index and then doing your inserts.
You have to be quite careful if you have concurrent access to SQLite, as the whole database i...
ORA-30926: unable to get a stable set of rows in the source tables
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This is usually caused by duplicates in the query specified in USING clause. This probably means that TABLE_A is a parent table and the same ROWID is returned several times.
You could quickly solve the problem by using a DISTINCT in yo...
Objective-C Static Class Level variables
...ing a Class Object in Apple's Objective-C docs.
– big_m
Oct 3 '11 at 16:02
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How to increment a datetime by one day?
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All of the current answers are wrong in some cases as they do not consider that timezones change their offset relative to UTC. So in some cases adding 24h is different from adding a calendar day.
Proposed solution
The follo...
PowerShell: Setting an environment variable for a single command only
On Linux, I can do:
7 Answers
7
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UILabel text margin [duplicate]
...ilIndent = -10.0f;
NSAttributedString *attrText = [[NSAttributedString alloc] initWithString:title attributes:@{ NSParagraphStyleAttributeName : style}];
UILabel * label = [[UILabel alloc] initWithFrame:someFrame];
label.numberOfLines = 0;
label.attributedText = attrText;
Here is the above e...
When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
...----- -------- -------------------------
0xCD Clean Memory Allocated memory via malloc or new but never
written by the application.
0xDD Dead Memory Memory that has been released with delete or free.
It is used to detect w...
How do you round to 1 decimal place in Javascript?
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You might want to create a function for this:
function roundedToFixed(_float, _digits){
var rounded = Math.pow(10, _digits);
return (Math.round(_float * rounded) / rounded).toFixed(_digits);
}
share
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Convert int to char in java
...a + '0');
System.out.println(b);
Here, we used '0' because chars are actually represented by ASCII values. '0' is a char and represented by the value of 48.
We typed (a + '0') and in order to add these up, Java converted '0' to its ASCII value which is 48 and a is 1 so the sum is 49. Then what w...
'System.Net.Http.HttpContent' does not contain a definition for 'ReadAsAsync' and no extension metho
I made a console app to consume a Web API I just made. The console app code does not compile. It gives me the compilation error:
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