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Check if table exists and if it doesn't exist, create it in SQL Server 2008
...
Something like this
IF NOT EXISTS (SELECT * FROM sys.objects
WHERE object_id = OBJECT_ID(N'[dbo].[YourTable]') AND type in (N'U'))
BEGIN
CREATE TABLE [dbo].[YourTable](
....
....
....
)
END
...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...or "ǽ" == "æ". For sorting this makes sense but could be surprising when selecting via equalities or dealing with unique indices - bugs.mysql.com/bug.php?id=16526
– Mat Schaffer
Mar 13 '15 at 15:22
...
Selecting an element in iFrame jQuery
...rame. All the elements in that loaded page have their tokenid-s. I need to select the elements by those tokenid-s. Means - I click on an element on the main page and select corresponding element in the page in the iFrame. With the help of jQuery I'm doing it in the following way:
...
Python Pandas: Get index of rows which column matches certain value
... [57]: idx
Out[57]: Int64Index([10, 40, 50], dtype='int64')
then you can select the rows using loc instead of iloc:
In [58]: df.loc[idx]
Out[58]:
BoolCol
10 True
40 True
50 True
[3 rows x 1 columns]
Note that loc can also accept boolean arrays:
In [55]: df.loc[df['BoolCol']]
Ou...
Select every Nth element in CSS
Is it possible to select, say, every fourth element in a set of elements?
4 Answers
4
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Set the selected index of a Dropdown using jQuery
...
First of all - that selector is pretty slow. It will scan every DOM element looking for the ids. It will be less of a performance hit if you can assign a class to the element.
$(".myselect")
To answer your question though, there are a few w...
How to drop columns by name in a data frame
..."z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset function : you can then use the - operator directly on a vector of column names, and you can even omit the quotes around the names !
R> subset(df, select=-c(z,u))
x y
1 1 2
2 2 3
3 3 4
4 4 ...
How to select only date from a DATETIME field in MySQL?
...e a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
...
Solutions for INSERT OR UPDATE on SQL Server
...nd PK violations you can use something like this:
begin tran
if exists (select * from table with (updlock,serializable) where key = @key)
begin
update table set ...
where key = @key
end
else
begin
insert into table (key, ...)
values (@key, ...)
end
commit tran
or
begin tran
upda...
LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method ca
... where p.Serial == strItem
select p;
The problem arises because ToString() isn't really executed, it is turned into a MethodGroup and then parsed and translated to SQL. Since there is no ToString() equivalent, the expression fails.
Note:
Make sure ...