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Difference between “read commited” and “repeatable read”
...like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any data. A concurrent transaction may up...
How to change navbar collapse threshold using Twitter bootstrap-responsive?
...tors.
– Mark Berry
Feb 27 '12 at 23:01
1
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Internet Explorer 11 disable “display intranet sites in compatibility view” via meta tag not working
...lJason Marsell
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Favourite performance tuning tricks [closed]
...possibly thousands of different asking prices.
Of these index choices, idx01 provides the faster path to satisfy the query:
CREATE INDEX idx01 ON dbo.inventory (price, color)
CREATE INDEX idx02 ON dbo.inventory (color, price)
This is because fewer cars will satisfy the price point than the color...
How to compare two dates?
...et's say you have the initial dates as strings like these:
date1 = "31/12/2015"
date2 = "01/01/2016"
You can do the following:
newdate1 = time.strptime(date1, "%d/%m/%Y") and newdate2 = time.strptime(date2, "%d/%m/%Y") to convert them to python's date format. Then, the comparison is obvious:
newdat...
Swapping column values in MySQL
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answered Feb 18 '09 at 0:01
Artem RussakovskiiArtem Russakovskii
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Are there best practices for (Java) package organization? [closed]
...ted Jul 5 '19 at 9:03
informatik01
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answered Jul 12 '10 at 6:44
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How to wait for a keypress in R?
...t = "[click on graph then follow top prompt to continue]")
Sys.sleep(0.01)
return(keyPressed)
}
onKeybd <- function(key)
{
keyPressed <<- key
}
xaxis=c(1:10) # Set up the x-axis.
yaxis=runif(10,min=0,max=1) # Set up the y-axis.
plot(xaxis,yaxis)
for (i in xaxis)
{
# On ea...
How can I custom-format the Autocomplete plug-in results?
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RajRaj
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Force R to stop plotting abbreviated axis labels - e.g. 1e+00 in ggplot2
In ggplot2 how can I stop axis labels being abbreviated - e.g. 1e+00, 1e+01 along the x axis once plotted? Ideally, I want to force R to display the actual values which in this case would be 1,10 .
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