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Laravel Eloquent Sum of relation's column
... is no price column. It looks like eloquent is not looking at that Product table at all....
– theAdmiral
Feb 10 '14 at 15:22
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Opposite of %in%: exclude rows with values specified in a vector
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If you look at the code of %in%
function (x, table) match(x, table, nomatch = 0L) > 0L
then you should be able to write your version of opposite. I use
`%not in%` <- function (x, table) is.na(match(x, table, nomatch=NA_integer_))
Another way is:
function (x,...
Update multiple columns in SQL
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Try this:
UPDATE table1
SET a = t2.a, b = t2.b, .......
FROM table2 t2
WHERE table1.id = t2.id
That should work in most SQL dialects, excluding Oracle.
And yes - it's a lot of typing - it's the way SQL does this.
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Storing images in SQL Server?
...pending on your use
If you decide to put your pictures into a SQL Server table, I would strongly recommend using a separate table for storing those pictures - do not store the employee photo in the employee table - keep them in a separate table. That way, the Employee table can stay lean and mean ...
UITableView Cell selected Color?
I have created a custom UITableViewCell . The table view is showing data fine. What I am stuck in is when user touches cell of tableview, then I want to show the background color of the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothi...
What was the strangest coding standard rule that you were forced to follow? [closed]
...h one you'll get, but I really really hate when I have to preface database table names with 'tbl'
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answered Oct 20 '08 at 11:41
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FIND_IN_SET() vs IN()
I have 2 tables in my database. One is for orders, and one is for companies.
6 Answers
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MySQL skip first 10 results
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There is an OFFSET as well that should do the trick:
SELECT column FROM table
LIMIT 10 OFFSET 10
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Fast way of counting non-zero bits in positive integer
...se that.
To answer a question in the comments, for bytes I'd use a lookup table. You can generate it at runtime:
counts = bytes(bin(x).count("1") for x in range(256)) # py2: use bytearray
Or just define it literally:
counts = (b'\x00\x01\x01\x02\x01\x02\x02\x03\x01\x02\x02\x03\x02\x03\x03\x04'...
What is the difference between HAVING and WHERE in SQL?
..., CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than ...