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Efficiently convert rows to columns in sql server
... yourtable
group by ColumnName, id
order by id
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = N'SELECT ' + @cols + N' from
(
select value, ColumnName
fr...
Adding multiple columns AFTER a specific column in MySQL
...pend to the table.
E.g: if you want to add count, log, status in the exact order after lastname, then the syntax would actually be:
ALTER TABLE users
ADD COLUMN log VARCHAR(12) NOT NULL AFTER lastname,
ADD COLUMN status INT(10) UNSIGNED NOT NULL AFTER lastname,
ADD COLUMN count SMALLINT(...
How do I remove repeated elements from ArrayList?
...t);
yourList.clear();
yourList.addAll(set);
Of course, this destroys the ordering of the elements in the ArrayList.
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Postgres DB Size Command
...g_size_pretty(pg_database_size(t1.datname)) as db_size
from pg_database t1
order by pg_database_size(t1.datname) desc;
If you intend the output to be consumed by a machine instead of a human, you can cut the pg_size_pretty() function.
...
What is the difference between a var and val definition in Scala?
...a number out of them. For example, if I have a queue with 2, 1, 3, in that order, I want to get back the number 213. Let's first solve it with a mutable.Queue:
def toNum(q: scala.collection.mutable.Queue[Int]) = {
var num = 0
while (!q.isEmpty) {
num *= 10
num += q.dequeue
}
num
}
...
Export query result to .csv file in SQL Server 2008
...utput mode, it doesn't affect the results if you already ran the query. In order for this to be reflected, you have to re-run the query. When you run it in "Results to File" mode, it should prompt you for where you would like to save the results.
– qJake
Jul 17...
HashSet vs LinkedHashSet
...
HashSet is unordered and unsorted Set.
LinkedHashSet is the ordered version of HashSet.
The only difference between HashSet and LinkedHashSet is that:
LinkedHashSet maintains the insertion order.
When we iterate through a HashSet, t...
Java 8 Iterable.forEach() vs foreach loop
... but "join" doesn't really seem like something that can be exexuted out-of order.
– Eugene Loy
May 19 '13 at 14:18
...
How to list active / open connections in Oracle?
...ogram
from v$session b, v$process a
where
b.paddr = a.addr
and type='USER'
order by spid;
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How to differ sessions in browser-tabs?
... Just a very late add-on, as to why: because I need to know this in order to know WHICH page on my site, for example, a user is focused on, and not just that they've gone from page to page (instead they went from tab to tab).
– Oliver Williams
Sep 23 '18...