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Get records with max value for each group of grouped SQL results
...the value for.
You avoid complicated subqueries that try to find the max() etc, and also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL ...
Use of an exclamation mark in a Git commit message via the command line
...r uses: typing complex commands, adding line breaks in your commit message etc.)
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What columns generally make good indexes?
...ata type that can be given some meaningful order, ie sorted (integer, date etc).
It does not matter if the data in a column is generally increasing. If you create an index on the column, the index will create it's own data structure that will simply reference the actual items in your table without...
What is the most efficient way to store tags in a database?
...egories eg : Programming languages : c#,vb,pearl. OS : windows7,dos ,linux etc
– Thunder
Feb 11 '11 at 6:03
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How to use SQL Order By statement to sort results case insensitive?
...so weird about case-sensitive string comparison. That's how the <, ==, etc. operators work by default in every programming language that I'm familiar with.
– dan04
Feb 13 '18 at 17:31
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How can I sort generic list DESC and ASC?
...pare because subtraction will wrap to positive for very large neg numbers, etc.". If you have b = int.MinValue and a = 1 (say), this will fail. Sometimes a method call is worth it.
– Wai Ha Lee
Dec 12 '15 at 21:56
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Detecting a redirect in ajax request?
...also may break down if the url gets munged (due to quoting/encoding issues etc) during the round trip... but for 99% of cases, this seems to get the job done.
On the server side, my specific case was a python application using the Pyramid web framework, and I used the following snippet:
import p...
What is the volatile keyword useful for?
...A is creating Singleton instance and just after creation, the CPU corrupts etc, all other threads will not be able to see the value of _instance as not null and they will believe it is still assigned null.
Why does this happen? Because reader threads are not doing any locking and until the writer...
What does Serializable mean?
...ntiated by a class, or just any "Software Objects" like assemblies, files, etc.? And if its the latter, is it just a standardized way of sending data between programs and environments?
– Sunburst275
Mar 20 at 14:27
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How to change highlighted occurrences color in Eclipse's sidebar?
...rences" enabled in Eclipse, placing the cursor on any type/variable/method/etc will highlight all occurrences in the text editor and place a faint bar in the right ruler to show you the location of other occurrences in the file.
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