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What's the best way to do a backwards loop in C/C#/C++?
...t, the problem with this approach is that an iterator doesn't allow you to selectively pick out items of the array - consider the situation where you wanted to navigate through a portion of an Array, but not the entire thing...
– jesses.co.tt
Feb 17 '16 at 21:5...
How to store arrays in MySQL?
... retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
share
|...
How to persist a property of type List in JPA?
...<List<String>, String> {
private static final String SPLIT_CHAR = ";";
@Override
public String convertToDatabaseColumn(List<String> stringList) {
return String.join(SPLIT_CHAR, stringList);
}
@Override
public List<String> convertToEntityAttri...
My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())
...t of all, there is C. In C, A a() is function declaration. For example, putchar has the following declaration. Normally, such declarations are stored in header files, however nothing stops you from writing them manually, if you know how the declaration of function looks like. The argument names are ...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...ction table
Example queries:
-- Getting all students for a class:
SELECT s.student_id, last_name
FROM student_classes sc
INNER JOIN students s ON s.student_id = sc.student_id
WHERE sc.class_id = X
-- Getting all classes for a student:
SELECT c.class_id, name
FROM s...
Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
... to a date by suffixing it with ::date. Here, in psql, is a timestamp:
# select '2010-01-01 12:00:00'::timestamp;
timestamp
---------------------
2010-01-01 12:00:00
Now we'll cast it to a date:
wconrad=# select '2010-01-01 12:00:00'::timestamp::date;
date
------------
201...
RegEx to find two or more consecutive chars
I need to determine if a string contains two or more consecutive alpha chars. Two or more [a-zA-Z] side by side.
Example:
...
static const vs #define
...l than a post-preprocessing "if" as the code need not be compilable if not selected by the preprocessor), use #undef-ine, redefine etc.
substituted text has to be exposed:
in the translation unit it's used by, which means macros in libraries for client use must be in the header, so make and other ...
How do I convert an integer to string as part of a PostgreSQL query?
...o 15 digits, you'll meed to cast to an 64 bit (8-byte) integer. Try this:
SELECT * FROM table
WHERE myint = mytext::int8
The :: cast operator is historical but convenient. Postgres also conforms to the SQL standard syntax
myint = cast ( mytext as int8)
If you have literal text you want to c...
Generate a random letter in Python
...tates If the relative weights or cumulative weights are not specified, the selections are made with equal probability. This would mean, that the distribution is the discrete uniform distribution (en.wikipedia.org/wiki/Discrete_uniform_distribution).
– Qaswed
Oc...