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Is there a way to select sibling nodes?
For some performance reasons, I am trying to find a way to select only sibling nodes of the selected node.
13 Answers
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Convert Unix timestamp into human readable date using MySQL
...
Use FROM_UNIXTIME():
SELECT
FROM_UNIXTIME(timestamp)
FROM
your_table;
See also: MySQL documentation on FROM_UNIXTIME().
share
|
improve...
SQL update fields of one table from fields of another one
...ic SQL is totally non-standard PostgreSQL syntax.
DO
$do$
BEGIN
EXECUTE (
SELECT
'UPDATE b
SET (' || string_agg( quote_ident(column_name), ',') || ')
= (' || string_agg('a.' || quote_ident(column_name), ',') || ')
FROM a
WHERE b.id = 123
AND a.id = b.id'
FROM i...
How to make vim paste from (and copy to) system's clipboard?
...system clipboard. On X11 systems both registers can be used. See :help x11-selection for more details, but basically the "* is analogous to X11's _PRIMARY_ selection (which usually copies things you select with the mouse and pastes with the middle mouse button) and "+ is analogous to X11's _CLIPBOAR...
“Inspect” a hover element?
...if this is just a problem on my PC or not, but I can't see the menu option selected via keyboard and the shortcut key (ctrl-shift-I) doesn't work while the dropdown menu is visible, so since inspect element is the last option on the dropdown, I used up-arrow key to wrap-around to the last item and h...
Select all 'tr' except the first one
How can I select all tr elements except the first tr in a table with CSS?
10 Answers
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MySQL: How to copy rows, but change a few fields?
...able
( Event_ID
, col2
...
)
SELECT "155"
, col2
...
FROM Table WHERE Event_ID = "120"
Here, the col2, ... represent the remaining columns (the ones other than Event_ID) in your table.
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Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to GROUP BY,...
Rank function in MySQL
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One option is to use a ranking variable, such as the following:
SELECT first_name,
age,
gender,
@curRank := @curRank + 1 AS rank
FROM person p, (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initializatio...
Importing a Maven project into Eclipse from Git
...t. M2Eclipse will help you along by prompting you on the Import menu.
Select the "Import..." context menu from the Package Explorer view
Select "Check out Maven projects from SCM" option under the Maven category
On the window that is presented choose the link "Find more SCM connectors in the m2...