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How do I generate random number for each row in a TSQL Select?
...mber.
I'd suggest using convert(varbinary,newid()) as the seed argument:
SELECT table_name, 1.0 + floor(14 * RAND(convert(varbinary, newid()))) magic_number
FROM information_schema.tables
newid() is guaranteed to return a different value each time it's called, even within the same batch, so usi...
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...
MySQL, Check if a column exists in a table with SQL
...query and I think it needs a small alteration to get it working properly.
SELECT *
FROM information_schema.COLUMNS
WHERE
TABLE_SCHEMA = 'db_name'
AND TABLE_NAME = 'table_name'
AND COLUMN_NAME = 'column_name'
That worked for me.
Thanks!
...
Cast int to varchar
...datatype, there is no varchar datatype that you can cast/convert data to:
select CAST(id as CHAR(50)) as col1
from t9;
select CONVERT(id, CHAR(50)) as colI1
from t9;
See the following SQL — in action — over at SQL Fiddle:
/*! Build Schema */
create table t9 (id INT, name VARCHAR(55));
ins...
Select all contents of textbox when it receives focus (Vanilla JS or jQuery)
What is a Vanilla JS or jQuery solution that will select all of the contents of a textbox when the textbox receives focus?
...
Function to Calculate Median in SQL Server
... in all cases. It also requires SQL 2012 or later.
DECLARE @c BIGINT = (SELECT COUNT(*) FROM dbo.EvenRows);
SELECT AVG(1.0 * val)
FROM (
SELECT val FROM dbo.EvenRows
ORDER BY val
OFFSET (@c - 1) / 2 ROWS
FETCH NEXT 1 + (1 - @c % 2) ROWS ONLY
) AS x;
Of course, just because o...
MySQL Query to select data from last week?
Hi I have a table with a date field and some other information.
I want to select all entries from the past week, (week start from Sunday).
...
Preventing an image from being draggable or selectable without using JS
Does anyone know of a way to make an image not draggable and not selectable -- at the same time -- in Firefox, without resorting to Javascript? Seems trivial, but here's the issue:
...
Eclipse: How do you change the highlight color of the currently selected method/expression?
...from the Annotation types list.
Then, be sure that Text as highlighted is selected, then choose the desired color.
And, a picture is worth a thousand words...
(source: coobird.net)
(source: coobird.net)
share
...
How does Trello access the user's clipboard?
...ually "access the user's clipboard", instead we help the user out a bit by selecting something useful when they press Ctrl+C.
Sounds like you've figured it out; we take advantage of the fact that when you want to hit Ctrl+C, you have to hit the Ctrl key first. When the Ctrl key is pressed, we pop ...