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Converting String to Int with Swift
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Can i ask why i am getting an error when i omit the '?' char? Why do i need to state 'a' as an optional?
– Manos Serifios
Jun 2 '16 at 20:16
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What are named pipes?
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#include <sys/types.h>
#include <sys/stat.h>
int mkfifo(const char *pathname, mode_t mode);
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how to listen to N channels? (dynamic select statement)
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You can do this using the Select function from the reflect package:
func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool)
Select executes a select operation described by the list of cases. Like
the Go select statement, it bl...
must appear in the GROUP BY clause or be used in an aggregate function
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Yes, this is a common aggregation problem. Before SQL3 (1999), the selected fields must appear in the GROUP BY clause[*].
To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname...
How to vertically align text inside a flexbox?
...-items: baseline. Good for different heights coming from different unicode chars etc.
– qräbnö
Jan 7 '19 at 16:50
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How do I perform an IF…THEN in an SQL SELECT?
How do I perform an IF...THEN in an SQL SELECT statement?
30 Answers
30
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How to concatenate text from multiple rows into a single text string in SQL server?
...y, John, Sam
2 Alaina, Edward
I used the following T-SQL:
SELECT Main.SubjectID,
LEFT(Main.Students,Len(Main.Students)-1) As "Students"
FROM
(
SELECT DISTINCT ST2.SubjectID,
(
SELECT ST1.StudentName + ',' AS [text()]
FR...
How to escape a JSON string containing newline characters using JavaScript?
I have to form a JSON string in which a value is having new line character. This has to be escaped and then posted using AJAX call. Can any one suggest a way to escape the string with JavaScript. I am not using jQuery.
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Using LIMIT within GROUP BY to get N results per group?
...to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
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| ID | GROUPED_YEAR |...
Is there any difference between GROUP BY and DISTINCT
...CT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I'm still baffled why it required it, but it does confirm there is some difference in the execution. As others point out, it also lets you GROUP BY columns no...