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How to get last N records with activerecord?
...e-wise - at least not up to Rails 3.1. SomeModel.last(5) will execute the select statement without a limit, returning all records of SomeModel to Ruby as an array, after which Ruby will pick out the last (5) elements. Efficiency-wise, currently, you want to use limit - particularly if you have pote...
Can you animate a height change on a UITableViewCell when selected?
... I would like it so that when the user clicks on a particular person (thus selecting the cell), the cell grows in height to display several UI controls for editing the properties of that person.
...
How can I do an UPDATE statement with JOIN in SQL Server?
...oesn't support MERGE):
ANSI/ISO:
update ud
set assid = (
select sale.assid
from sale
where sale.udid = ud.id
)
where exists (
select *
from sale
where sale.udid = ud.id
);
MySQL:
update ud u
inner join sale s on
u.id = s.udid
...
Get size of all tables in database
...
SELECT
t.NAME AS TableName,
s.Name AS SchemaName,
p.rows,
SUM(a.total_pages) * 8 AS TotalSpaceKB,
CAST(ROUND(((SUM(a.total_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS TotalSpaceMB,
SUM(a.used_pa...
CASCADE DELETE just once
...you want to cascade.
DELETE FROM some_child_table WHERE some_fk_field IN (SELECT some_id FROM some_Table);
DELETE FROM some_table;
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What does the “+” (plus sign) CSS selector mean?
...
See adjacent selectors on W3.org.
In this case, the selector means that the style applies only to paragraphs directly following another paragraph.
A plain p selector would apply the style to every paragraph in the page.
This will onl...
How do I select a random value from an enumeration?
Given an arbitrary enumeration in C#, how do I select a random value?
9 Answers
9
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Tracking CPU and Memory usage per process
...tility to save the performance data for your inspection later. To do this, select "Performance Logs and Alerts" in the left-hand panel. (It's right under the System Monitor console which provides us with the above mentioned counters. If it is not there, click "File" > "Add/remove snap-in", click ...
What is the difference between the states selected, checked and activated in Android?
...below added):
... For example, in a list view with single or multiple selection
enabled, the views in the current selection set are activated. (Um,
yeah, we are deeply sorry about the terminology here.) The activated
state is propagated down to children of the view it is set on.
So here...
OnChange event handler for radio button (INPUT type=“radio”) doesn't work as one value
...ame attribute myRadios to read the variable prev which holds the currently selected radio. A comparison is done within each click handler to decide if the clicked radio is the same as the one stored in prev and if not then the currently clicked radio is stored there. Within the click handler, you ha...