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MySQL SELECT WHERE datetime matches day (and not necessarily time)
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NEVER EVER use a selector like DATE(datecolumns) = '2012-12-24' - it is a performance killer:
it will calculate DATE() for all rows, including those, that don't match
it will make it impossible to use an index for the query
It is much fas...
Reset auto increment counter in postgres
... Does anyone know why ALTER SEQUENCE product_id_seq RESTART WITH (SELECT MAX(id) from product); Doesn't work? The only way I found is to use two separate queries.
– Chris Huang-Leaver
Dec 20 '18 at 3:14
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Force CloudFront distribution/file update
...Click on Blank Function (custom)
Step 3
Click on empty (stroked) box and select S3 from combo
Step 4
Select your Bucket (same as for CloudFront distribution)
Step 5
Set an Event Type to "Object Created (All)"
Step 6
Set Prefix and Suffix or leave it empty if you don't know what it is.
Step ...
Is it possible to use Java 8 for Android development?
...ce
Click on the Android SDK Manager button which is located on the toolbar
Select Android SDK Build tools Rev. 19.1 and Android Support Library only. Un-select everything else and install these two packages.
If everything goes well, ADT will be up and running.
The installation of the following to...
Data binding to SelectedItem in a WPF Treeview
How can I retrieve the item that is selected in a WPF-treeview? I want to do this in XAML, because I want to bind it.
20 An...
What makes a SQL statement sargable?
...non-sargable is to include a field inside a function in the where clause:
SELECT ... FROM ...
WHERE Year(myDate) = 2008
The SQL optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use:
WHERE myDat...
JComboBox Selection Change Listener?
...istener() will work, too. You may get 2 ItemEvents, though, one for the deselection of the previously selected item, and another for the selection of the new item. Just don't use both event types!
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Eclipse does not highlight matching variables
...y:
window > preferences > java > editor > mark occurrences
Select all options available there.
Also go to:
Preferences > General > Editors > Text Editors > Annotations
Compare the settings for 'Occurrences' and 'Write Occurrences'
Make sure that you don't have the 'T...
Select the values of one property on all objects of an array in PowerShell
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I think you might be able to use the ExpandProperty parameter of Select-Object.
For example, to get the list of the current directory and just have the Name property displayed, one would do the following:
ls | select -Property Name
This is still returning DirectoryInfo or FileInfo obje...
Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to GROUP BY,...