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What columns generally make good indexes?
...earching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such columns should be indexed against which yo...
LINQ to SQL Left Outer Join
...table), where-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
s...
Why can't radio buttons be “readonly”?
...ton by disabling only the un-checked radio buttons. It keeps the user from selecting a different value, and the checked value will always post on submit.
Using jQuery to make readonly:
$(':radio:not(:checked)').attr('disabled', true);
This approach also worked for making a select list readonly, ...
Easiest way to copy a table from one database to another?
...
CREATE TABLE db1.table1 SELECT * FROM db2.table1
where db1 is the destination and db2 is the source
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How to remove a web site from google analytics
...e awhile to figure out.
Go to the Admin tab.
In the middle column, select the web property that you want to delete from the dropdown.
In the right-hand column, click on "View Settings." ("Property Settings" in dec. 2015)
At the bottom of the next page, select "Delete this view."
...
How to Delete using INNER JOIN with SQL Server?
...helpful for you -
DELETE FROM dbo.WorkRecord2
WHERE EmployeeRun IN (
SELECT e.EmployeeNo
FROM dbo.Employee e
WHERE ...
)
Or try this -
DELETE FROM dbo.WorkRecord2
WHERE EXISTS(
SELECT 1
FROM dbo.Employee e
WHERE EmployeeRun = e.EmployeeNo
AND ....
)
...
Can I combine :nth-child() or :nth-of-type() with an arbitrary selector?
Is there a way to select every nth child that matches (or does not match) an arbitrary selector ? For example, I want to select every odd table row, but within a subset of the rows:
...
Comparing date ranges
... range_start, here's some simple SQL to retrieve all the matching rows:
SELECT *
FROM periods
WHERE NOT (range_start > @check_period_end
OR range_end < @check_period_start)
Note the NOT in there. Since the two simple rules finds all the non-matching rows, a simple NOT will reve...
sed error: “invalid reference \1 on `s' command's RHS”
...
Sorry. The edit raises the error: sed: -e expression #7, char 58: Invalid range end. @Denis' answer works.
– JJD
May 19 '13 at 18:29
...
When restoring a backup, how do I disconnect all active connections?
... the steps (via: Tim Leung)
Right-click the server in Object Explorer and select 'Activity Monitor'.
When this opens, expand the Processes group.
Now use the drop-down to filter the results by database name.
Kill off the server connections by selecting the right-click 'Kill Process' option.
...