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Subtract one day from datetime
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Try this
SELECT DATEDIFF(DAY, DATEADD(day, -1, '2013-03-13 00:00:00.000'), GETDATE())
OR
SELECT DATEDIFF(DAY, DATEADD(day, -1, @CreatedDate), GETDATE())
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How to Join to first row
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SELECT Orders.OrderNumber, LineItems.Quantity, LineItems.Description
FROM Orders
JOIN LineItems
ON LineItems.LineItemGUID =
(
SELECT TOP 1 LineItemGUID
FROM LineItems
W...
How to use index in select statement?
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If you want to test the index to see if it works, here is the syntax:
SELECT *
FROM Table WITH(INDEX(Index_Name))
The WITH statement will force the index to be used.
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Insert into … values ( SELECT … FROM … )
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Try:
INSERT INTO table1 ( column1 )
SELECT col1
FROM table2
This is standard ANSI SQL and should work on any DBMS
It definitely works for:
Oracle
MS SQL Server
MySQL
Postgres
SQLite v3
Teradata
DB2
Sybase
Vertica
HSQLDB
H2
AWS RedShift
SA...
How do I check how many options there are in a dropdown menu?
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var length = $('#mySelectList').children('option').length;
or
var length = $('#mySelectList > option').length;
This assumes your <select> list has an ID of mySelectList.
http://api.jquery.com/length/
http://api.jquery.com/childr...
How to generate a range of numbers between two numbers?
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Select non-persisted values with the VALUES keyword. Then use JOINs to generate lots and lots of combinations (can be extended to create hundreds of thousands of rows and beyond).
SELECT ones.n + 10*tens.n + 100*hundreds.n +...
Expert R users, what's in your .Rprofile? [closed]
...se it might breaks my coauthors' code, I wish it was the default. Why?
1) Character vectors use less memory (but only barely);
2) More importantly, we would avoid problems such as:
> x <- factor(c("a","b","c"))
> x
[1] a b c
Levels: a b c
> x <- c(x, "d")
> x
[1] "1" "2" "3" "...
MySQL Great Circle Distance (Haversine formula)
...ults. To search by kilometers instead of miles, replace 3959 with 6371.
SELECT id, ( 3959 * acos( cos( radians(37) ) * cos( radians( lat ) )
* cos( radians( lng ) - radians(-122) ) + sin( radians(37) ) * sin(radians(lat)) ) ) AS distance
FROM markers
HAVING distance < 25
ORDER BY distance ...
Convert to absolute value in Objective-C
...+ programs too.)
(Alas, there is no habs(short) function. Or scabs(signed char) for that matter...)
Apple's and GNU's Objective-C headers also include an ABS() macro which is type-agnostic. I don't recommend using ABS() however as it is not guaranteed to be side-effect-safe. For instance, ABS(a+...
Is there a way to change the environment variables of another process in Unix?
...ocesses.
Suppose that you write your own shared library which implements 'char *getenv'. Then, you set up 'LD_PRELOAD' or 'LD_LIBRARY_PATH' env. vars so that both your processes are run with your shared library preloaded.
This way, you will essentially have a control over the code of the 'getenv' ...