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Reference alias (calculated in SELECT) in WHERE clause
The calculated value BalanceDue that is set as a variable in the list of selected columns cannot be used in the WHERE clause.
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SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
mysql -> insert into tbl (select from another table) and some default values [duplicate]
As the title says, I am trying to insert into one table selecting values from another table and some default values.
5 Ans...
Is it possible to center text in select box?
...you could style the dropdown:
https://www.filamentgroup.com/lab/jquery-ui-selectmenu-an-aria-accessible-plugin-for-styling-a-html-select.html
This plugin hides the select element, and creates span elements etc on the fly to display a custom drop down list style. I'm quite confident you'd be able t...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
How can I disable the UITableView selection?
When you tap a row in a UITableView , the row is highlighted and selected. Is it possible to disable this so tapping a row does nothing?
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Lists in ConfigParser
... @wim You would need to implement a way to escape the delimiter character if it can be a legal character. (And a way to escape whatever character you use for escaping.)
– jamesdlin
Aug 29 '17 at 3:25
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Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...
@synthesize vs @dynamic, what are the differences?
... [invocation setReturnValue:&obj];
}
}
@end
int main(int argc, char **argv)
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
Book *book = [[Book alloc] init];
printf("%s is written by %s\n", [book.title UTF8String], [book.author UTF8String]);
book.title = @"...