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must appear in the GROUP BY clause or be used in an aggregate function
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Yes, this is a common aggregation problem. Before SQL3 (1999), the selected fields must appear in the GROUP BY clause[*].
To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname...
How to bind RadioButtons to an enum?
..., Converter={StaticResource enumBooleanConverter}, ConverterParameter=FirstSelection}">first selection</RadioButton>
<RadioButton IsChecked="{Binding Path=VeryLovelyEnum, Converter={StaticResource enumBooleanConverter}, ConverterParameter=TheOtherSelection}">the other selection&...
How do I remedy “The breakpoint will not currently be hit. No symbols have been loaded for this docu
...ocess. Locate the one you want to get debug info for. Right-click it and select Symbol Load Information. You'll get a dialog that lists all the directories where it looked for the .pdb file for the assembly. Verify that list against the actual .pdb location. Make sure it doesn't find an old one...
How do you manually execute SQL commands in Ruby On Rails using NuoDB
...Base.connection.execute("foo")
with "foo" being the sql statement( i.e. "SELECT * FROM table").
This command will return a set of values as a hash and put them into the results variable.
So on my rails application_controller.rb I added this:
def execute_statement(sql)
results = ActiveRecord::...
Inspect hovered element in Chrome?
...er over the element to bring up the tooltip, right click as if you were to select 'Inspect Element'. Leaving that context menu open, move the focus over to the dev tools. The html for the tooltip should show up next to the element its a tooltip for in the HTML. Then you can look at it as if it were ...
Changing the status bar text color in splash screen iOS 7
...ng things for getting light color status bar throughout the application.
Select the name of the project in the project navigator.
Select the name of a target from the list in the left column of the project editor.
Click General at the top of the project editor.
Set Status Bar Style -> Light
I...
SQL - using alias in Group By
... following order:
FROM clause
WHERE clause
GROUP BY clause
HAVING clause
SELECT clause
ORDER BY clause
For most relational database systems, this order explains which names (columns or aliases) are valid because they must have been introduced in a previous step.
So in Oracle and SQL Server, you...
The import android.support cannot be resolved
...Libraries tab. There click the Add External JARs Button on the Right pane.
Select the android-support-v4.jar file, usually the path for the Jar file is :
YOUR_DRIVE\android-sdks\extras\android\support\v4\android-support-v4.jar
After adding android-support-v4.jar Library, navigate to the Order and E...
Can “list_display” in a Django ModelAdmin display attributes of ForeignKey fields?
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@marcelm that’s what select_related is for. the get_queryset() of the UserAdmin will have to be overwritten.
– interDist
Jul 17 '17 at 21:38
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Pandas every nth row
...] # Excludes every 3rd row starting from 0
df2 = df[df.index % 3 == 0] # Selects every 3rd raw starting from 0
This arithmetic based sampling has the ability to enable even more complex row-selections.
This assumes, of course, that you have an index column of ordered, consecutive, integers star...