大约有 5,800 项符合查询结果(耗时:0.0135秒) [XML]
SQL WHERE ID IN (id1, id2, …, idn)
...izes like below:
Divide you list of Ids into chunks of fixed number, say 100
Chunk size should be decided based upon the memory size of your server
Suppose you have 10000 Ids, you will have 10000/100 = 100 chunks
Process one chunk at a time resulting in 100 database calls for select
Why should y...
Make footer stick to bottom of page correctly [duplicate]
...ddle and SO snippet:
html {
position: relative;
min-height: 100%;
}
body {
margin: 0 0 100px;
/* bottom = footer height */
padding: 25px;
}
footer {
background-color: orange;
position: absolute;
left: 0;
bottom: 0;
height: 100px;
wi...
jQuery trigger file input
... positioning it outside the viewport by setting position:absolute and top:-100px; and voilà it works.
see http://jsfiddle.net/DSARd/1/
call it a hack.
Hope that works for you.
share
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improve th...
Heroku free account limited?
...o requests. If each instance of your application can serve each request in 100ms, then you get 600 requests/minute with the free account.
Your application code and its assets (the slug) are limited to 300 MB in total. Your application also has access to the local filesystem, which can serve as an e...
How to force R to use a specified factor level as reference in a regression?
...e the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor b in DF by use of t...
Null coalescing in powershell
...ssignment, and ternary operators in Powershell.
Null Coalescing
$null ?? 100 # Result is 100
"Evaluated" ?? (Expensive-Operation "Not Evaluated") # Right side here is not evaluated
Null Conditional Assignment
$x = $null
$x ??= 100 # $x is now 100
$x ??= 200 # $x remains 100
Terna...
Calculating frames per second in a game
...
100
You need a smoothed average, the easiest way is to take the current answer (the time to draw t...
What's the difference between `1L` and `1`?
...re adding 1 to an integer vector turns it into a double vector:
x <- 1:100
typeof(x) # integer
y <- x+1
typeof(y) # double, twice the memory size
object.size(y) # 840 bytes (on win64)
z <- x+1L
typeof(z) # still integer
object.size(z) # 440 bytes (on win64)
...but also note that work...
File upload progress bar with jQuery
...t.loaded / evt.total;
percentComplete = parseInt(percentComplete * 100);
console.log(percentComplete);
if (percentComplete === 100) {
}
}
}, false);
return xhr;
},
url: posturlfile,
type: "POST",
data: JSON.stringify(fileuploaddata),
conten...
Select SQL Server database size
... MB
Function:
ALTER FUNCTION [dbo].[GetDBSize]
(
@db_name NVARCHAR(100)
)
RETURNS TABLE
AS
RETURN
SELECT
database_name = DB_NAME(database_id)
, log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2))
, row_size_mb = CAST(SUM(CASE...
