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Delimiters in MySQL
...TABLE tablea (
col1 INT,
col2 INT
);
INSERT INTO tablea
SELECT * FROM table1;
CREATE TABLE tableb (
col1 INT,
col2 INT
);
INSERT INTO tableb
SELECT * FROM table2;
/* whole procedure ends with the custom delimiter */
END$$
/* Finally, reset the delimiter to...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...-date), sum)
# summarising a specific set of non-grouping variables using select_helpers
# see ?select_helpers for more options
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(starts_with('x')), sum)
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(matches('.*...
Execute SQLite script
...return to my shell script, I think this works well:
$ sqlite3 example.db 'SELECT * FROM some_table;'
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Xcode 4.2 debug doesn't symbolicate stack call
...y setting it at the END of your didFinishLaunchingWithOptions function (or selectively disabling 3rd party libraries). Or better yet, set a symbolic break point on NSSetUncaughtExceptionHandler to quickly see who is calling it. What you may want to do is to modify your current one rather than adding...
How to remove elements from a generic list while iterating over it?
...
Select the elements you do want rather than trying to remove the elements you don't want. This is so much easier (and generally more efficient too) than removing elements.
var newSequence = (from el in list
...
What is The difference between ListBox and ListView
...ew, but you can easily create your own.
Another difference is the default selection mode: it's Single for a ListBox, but Extended for a ListView
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How can I write output from a unit test?
...ling to find it, it's in the Text Explorer, bottom section. When a test is selected, it shows you the result with "Elapsed time: xxx". Below that is the "Output" link.
– kevin
May 18 '14 at 11:00
...
Having both a Created and Last Updated timestamp columns in MySQL 4.0
...dated) values(null, null);
Query OK, 1 row affected (0.06 sec)
mysql> select * from test_table;
+----+---------------------+---------------------+
| id | stamp_created | stamp_updated |
+----+---------------------+---------------------+
| 2 | 2009-04-30 09:44:35 | 2009-04-30 09:4...
What is the difference between jQuery's mouseout() and mouseleave()?
...
Event Mouseout will trigger when mouse leaves the selected element and also when mouse leaves it's child elements also.
Event Mouseleave element will trigger when pointer will leave the selected element only.
Reference: W3School
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How do I create a simple 'Hello World' module in Magento?
...ck our work). In the admin application
Go to System->Cache Management
Select Refresh from the All Cache menu
Click Save Cache settings
Now, we make sure that Magento knows about the module
Go to System->Configuration
Click Advanced
In the "Disable modules output" setting box, look for yo...