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What is the size of an enum in C?
...tum's answer, which references C99, says that an enum may be as small as a char.
– Frank Kusters
Sep 15 '17 at 6:46
...
Schema for a multilanguage database
...t PostGreSQL with hstore), you can't pass a parameter language, and say:
SELECT ['DESCRIPTION_' + @in_language] FROM T_Products
So you have to do this:
SELECT
Product_UID
,
CASE @in_language
WHEN 'DE' THEN DESCRIPTION_DE
WHEN 'SP' THEN DESCRIPTION_SP
EL...
What is the difference between sigaction and signal?
...s defined in the C standard. Nevertheless, it has a number of undesirable characteristics that sigaction() avoids - unless you use the flags explicitly added to sigaction() to allow it to faithfully simulate the old signal() behaviour.
The signal() function does not (necessarily) block other signa...
Inserting data into a temporary table
...
INSERT INTO #TempTable (ID, Date, Name)
SELECT id, date, name
FROM physical_table
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MySQL SELECT only not null values
Is it possible to do a select statement that takes only NOT NULL values?
9 Answers
9
...
How can I use map and receive an index as well in Scala?
... as follows:
import TraversableUtil._
List('a','b','c').map(doIndexed((i, char) => char + i))
which results in the list
List(97, 99, 101)
This way, you can use the usual Traversable-functions at the expense of wrapping your effective function. The overhead is the creation of the memoizing o...
How do I check OS with a preprocessor directive?
...eturn a name of platform, if determined, otherwise - an empty string
const char *get_platform_name() {
return (PLATFORM_NAME == NULL) ? "" : PLATFORM_NAME;
}
int main(int argc, char *argv[]) {
puts(get_platform_name());
return 0;
}
Tested with GCC and clang on:
Debian 8
Windows (Min...
An explicit value for the identity column in table can only be specified when a column list is used
...tead of
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table
SELECT *
FROM source_table;
SET IDENTITY_INSERT archive_table OFF;
you need to write
SET IDENTITY_INSERT archive_table ON;
INSERT INTO archive_table (field1, field2, ...)
SELECT field1, field2, ...
FROM source_table;...
Identify if a string is a number
...$")
If you just want to know if it has one or more numbers mixed in with characters, leave off the ^ + and $.
Regex.IsMatch(input, @"\d")
Edit:
Actually I think it is better than TryParse because a very long string could potentially overflow TryParse.
...
LINQ's Distinct() on a particular property
...
(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
HashSet<TKey> seenKeys = new HashSet<TKey>();
foreach (TSource element in source)
{
if (seenKeys.Add(keySelector(element)))
{
yield return element;
}
...