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Please explain the exec() function and its family
... family have different behaviours:
l : arguments are passed as a list of strings to the main()
v : arguments are passed as an array of strings to the main()
p : path/s to search for the new running program
e : the environment can be specified by the caller
You can mix them, therefore you have:
...
How to change a string into uppercase
I have problem in changing a string into uppercase with Python. In my research, I got string.ascii_uppercase but it doesn't work.
...
Group query results by month and year in postgresql
...ht make sense to use date_trunc, but in some cases having a formatted date string is preferable, and if you're using a performant data warehouse the additional computation might not be a deal breaker. For example, if you are running a quick analytics report using redshift, and it usually takes 3 sec...
Are there disadvantages to using a generic varchar(255) for all text-based fields?
... (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
...
How to bind inverse boolean properties in WPF?
... of effort to separate what they feel is "code" from those poor designers. Extra extra painful when I’m both the coder and the designer.
– Roman Starkov
Apr 14 '12 at 14:48
10
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Equals(=) vs. LIKE
... these operators!
= is a comparison operator that operates on numbers and strings. When comparing strings, the comparison operator compares whole strings.
LIKE is a string operator that compares character by character.
To complicate matters, both operators use a collation which can have important...
How to find memory leak in a C++ code/project?
...you allocated:
char* str = new char [30]; // Allocate 30 bytes to house a string.
delete [] str; // Clear those 30 bytes and make str point nowhere.
2
Reallocate memory only if you've deleted. In the code below, str acquires a new address with the second allocation. The first address is lost ir...
How to remove first 10 characters from a string?
How to ignore the first 10 characters of a string?
12 Answers
12
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What to do with “Unexpected indent” in python?
... statement). All lines of code in a block must start with exactly the same string of whitespace. For instance:
>>> def a():
... print "foo"
... print "bar"
IndentationError: unexpected indent
This one is especially common when running python interactively: make sure you don't put a...
How to persist a property of type List in JPA?
... should anyone be looking for an alternative solution where you store your string lists as one field in your database, here's how I solved that. Create a Converter like this:
import java.util.Arrays;
import java.util.List;
import javax.persistence.AttributeConverter;
import javax.persistence.Conve...