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How do I (or can I) SELECT DISTINCT on multiple columns?
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SELECT DISTINCT a,b,c FROM t
is roughly equivalent to:
SELECT a,b,c FROM t GROUP BY a,b,c
It's a good idea to get used to the GROUP BY syntax, as it's more powerful.
For your query, I'd do it like this:
UPDATE sale...
Get first day of week in SQL Server
...in that there should be some sensible logic built in to round up or down:
SELECT DATEDIFF(YEAR, '2010-01-01', '2011-12-31');
SELECT DATEDIFF(YEAR, '2010-12-31', '2011-01-01');
To answer how to get a Sunday:
If you want a Sunday, then pick a base date that's not a Monday but rather a Sunday. For ...
postgresql - sql - count of `true` values
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SELECT COALESCE(sum(CASE WHEN myCol THEN 1 ELSE 0 END),0) FROM <table name>
or, as you found out for yourself:
SELECT count(CASE WHEN myCol THEN 1 END) FROM <table name>
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SELECT * WHERE NOT EXISTS
...uming these tables should be joined on employeeID, use the following:
SELECT *
FROM employees e
WHERE NOT EXISTS
(
SELECT null
FROM eotm_dyn d
WHERE d.employeeID = e.id
)
You can join these tables with a LEFT JOIN keyword and filter out the...
Using DISTINCT and COUNT together in a MySQL Query
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use
SELECT COUNT(DISTINCT productId) from table_name WHERE keyword='$keyword'
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Search for selection in vim
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Check this Vim tip: Search for visually selected text
Or you can simply yank the selected text with y and go to search mode /, then you can paste the last yanked text with Ctrl+R 0
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Iterate through options
I have a <select> element in HTML. This element represents a drop down list. I'm trying to understand how to iterate through the options in the <select> element via JQuery.
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Search for all occurrences of a string in a mysql database [duplicate]
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In phpMyAdmin a 'Search' feature is available:
Select particular database not table.
Click 'Search' tab
Enter the search term you want
Select the tables you want to search in
phpMyAdmin screen shot:
The 'Search' feature is also available in MySQL Workbench:
Databa...
✔ Checkmark selected row in UITableViewCell
...pment newbie. I want to add a checkmark to my UITableViewCell when it is selected. The checkmark should be removed when another row is selected. How would I do this?
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Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...