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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
The import javax.servlet can't be resolved [duplicate]
...ibraries tab
Click Add External JARs...
Browse to find servlet-api.jar and select it.
Click OK to update the build path.
Or, if you copy the JAR into your project:
Right-click the project, click Properties.
Choose Java Build Path.
Click Add JARs...
Find servlet-api.jar in your project and select...
How to sleep for five seconds in a batch file/cmd [duplicate]
...specify the timeout in seconds and the /D parameter to specify the default selection and ignore then selected choice.
The one thing that might be an issue is if the user types one of the choice characters before the timeout period elapses. A partial work-around is to obfuscate the situation -- use ...
Working copy locked error in tortoise svn while committing
...em. I did this lots of time... :)
Note. Make sure "Break locks" option is selected in the Cleanup dialog.
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Download old version of package with NuGet
...t-Package -ListAvailable [-Source X] -Filter Common.Logging -AllVersions | select version, dependencies (or '| get-member' to see all the properties)
– Curtis Yallop
Jan 25 '13 at 21:49
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jquery data selector
I need to select elements based on values stored in an element's .data() object. At a minimum, I'd like to select top-level data properties using selectors, perhaps like this:
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Aggregate function in an SQL update query?
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UPDATE t1
SET t1.field1 = t2.field2Sum
FROM table1 t1
INNER JOIN (select field3, sum(field2) as field2Sum
from table2
group by field3) as t2
on t2.field3 = t1.field3
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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Find all elements on a page whose element ID contains a certain text using jQuery
... $(this).doStuff();
});
Note the asterisk '*' at the beginning of the selector matches all elements.
See the Attribute Contains Selectors, as well as the :visible and :hidden selectors.
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jQuery Set Cursor Position in Text Area
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I have two functions:
function setSelectionRange(input, selectionStart, selectionEnd) {
if (input.setSelectionRange) {
input.focus();
input.setSelectionRange(selectionStart, selectionEnd);
}
else if (input.createTextRange) {
var range = inpu...