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'Must Override a Superclass Method' Errors after importing a project into Eclipse
... preferences and set the Java compiler level to 1.6 and also make sure you select JRE 1.6 to execute your program from Eclipse.
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Shortcut to Apply a Formula to an Entire Column in Excel [closed]
If I select a cell containing a formula, I know I can drag the little box in the right-hand corner downwards to apply the formula to more cells of the column. Unfortunately, I need to do this for 300,000 rows!
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Eclipse copy/paste entire line keyboard shortcut
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Ctrl-Alt-Down: copies current line or selected lines to below
Ctrl-Alt-Up:: copies current line or selected lines to above
Ctrl-Shift-L: brings up a List of shortcut keys
See Windows/Preference->General->Keys.
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MySQL Results as comma separated list
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You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
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LINQ: When to use SingleOrDefault vs. FirstOrDefault() with filtering criteria
... When I ran a SingleOrDefault through LinqPad and VS, I never got SELECT TOP 2, with FirstOrDefault I was able to get SELECT TOP 1, but as far as I can tell you do not get SELECT TOP 2.
– Jamie R Rytlewski
Dec 22 '11 at 15:04
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Set selected radio from radio group with a value
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With the help of the attribute selector you can select the input element with the corresponding value. Then you have to set the attribute explicitly, using .attr:
var value = 5;
$("input[name=mygroup][value=" + value + "]").attr('checked', 'checked');
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MySQL SELECT WHERE datetime matches day (and not necessarily time)
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NEVER EVER use a selector like DATE(datecolumns) = '2012-12-24' - it is a performance killer:
it will calculate DATE() for all rows, including those, that don't match
it will make it impossible to use an index for the query
It is much fas...
Visual Studio - Shortcut to Navigate to Solution Explorer
Is there a keyboard shortcut in Visual Studio (aside from CTRL + TAB and selection) that would take me from inside a document directly into the solution explorer? I don't want to customize any shortcuts or change any default behavior.
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How do I see all foreign keys to a table or column?
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For a Table:
SELECT
TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME, REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME
FROM
INFORMATION_SCHEMA.KEY_COLUMN_USAGE
WHERE
REFERENCED_TABLE_SCHEMA = '<database>' AND
REFERENCED_TABLE_NAME = '<...
Extract a dplyr tbl column as a vector
...2 3.62 3.54 4.11
A nice way to do this in v0.2 of dplyr:
iris2 %>% select(Species) %>% collect %>% .[[5]]
Or if you prefer:
iris2 %>% select(Species) %>% collect %>% .[["Species"]]
Or if your table isn't too big, simply...
iris2 %>% collect %>% .[["Species"]]
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