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Two single-column indexes vs one two-column index in MySQL?
... the statement I provided.
Additionally, MySQL can only use one index per SELECT so a covering index would be the best means of optimizing your queries.
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How can I see the SQL that will be generated by a given ActiveRecord query in Ruby on Rails
... write a plugin that would do something like: SampleModel.find(:all, :select => "DISTINCT(*)", :conditions => ["date > #{self.date}"], :limit => 1, :order => 'date', :group => "date").show_generated_sql and have this call the construct_finder_sql method.
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Version vs build in Xcode
...ey are the same values.
When viewing the Info tab, if you right-click and select Show Raw Keys/Values, you'll see the actual names are CFBundleShortVersionString (Version) and CFBundleVersion (Build).
The Version is usually used how you appear to have been using it with Xcode 3. I'm not sure on wh...
UltiSnips and YouCompleteMe
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" make YCM compatible with UltiSnips (using supertab)
let g:ycm_key_list_select_completion = ['<C-n>', '<Down>']
let g:ycm_key_list_previous_completion = ['<C-p>', '<Up>']
let g:SuperTabDefaultCompletionType = '<C-n>'
" better key bindings for UltiSnipsExpandTrigger
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T-SQL: Selecting rows to delete via joins
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DELETE FROM TableA a WHERE [filter condition on TableA]
AND (a.BId IN (SELECT a.BId FROM TableB b JOIN TableA a
ON a.BId = b.BId
WHERE [filter condition on TableB]))
(Note Interbase doesn't support the AS keyword for aliases)
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“Cannot evaluate expression because the code of the current method is optimized” in Visual Studio 20
...this issue when I was using VS 2010. My solution configuration has (Debug) selected. I resolved this by unchecking the Optimize Code property under project properties.
Project (right Click)=> Properties => Build (tab) => uncheck Optimize code
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app-release-unsigned.apk is not signed
...ettings.
Go to Signing Tab. Add a signing config and fill in information. Select your keychain as well.
Go to Build Type tab. Select release mode and set:
-Debuggable to true.
-Signing Config to the config. (The one you just created).
Sync your gradle. Enjoy!
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SQL Server String or binary data would be truncated
...ur source query and execute Max(Len( source col )) on each column. I.e.,
Select Max(Len(TextCol1))
, Max(Len(TextCol2))
, Max(Len(TextCol3))
, ...
From ...
Then compare those lengths to the data type lengths in your destination table. At least one, exceeds its destination column leng...
Apache Tomcat Not Showing in Eclipse Server Runtime Environments
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For version 2019-09, in drop down select: 2019-09 - download.eclipse.org/releases/2019-09 and install both: JST Server Adapters and JST Server Adapters extensions
– Olivier Royo
Nov 14 '19 at 8:07
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Is there a way to create xxhdpi, xhdpi, hdpi, mdpi and ldpi drawables from a large scale image?
...er:
To use it after installed, right click your res/drawable folder and select New > Batch Drawable Import:
Then select your image via the + button and set the Resolution to be xxhdpi (or whatever the resolution of your source image is).
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