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Postgres: How to do Composite keys?
I cannot understand the syntax error in creating a composite key. It may be a logic error, because I have tested many varieties.
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Are PostgreSQL column names case-sensitive?
I have a db table say, persons in Postgres handed down by another team that has a column name say, "first_Name" . Now am trying to use PG commander to query this table on this column-name.
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Set Django IntegerField by choices=… name
When you have a model field with a choices option you tend to have some magic values associated with human readable names. Is there in Django a convenient way to set these fields by the human readable name instead of the value?
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Android: When is onCreateOptionsMenu called during Activity lifecycle?
I put a couple of breakpoints in onCreate (one at the beginning, and one at the end of the method), and I also put one at the beginning of onCreateOptionsMenu . The onCreate method is called first, and before it finishes onCreateOptionsMenu is called.
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Django: Set foreign key using integer?
Is there a way to set foreign key relationship using the integer id of a model? This would be for optimization purposes.
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You have already activated X, but your Gemfile requires Y
When running rake I get this error:
7 Answers
7
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Understanding Fragment's setRetainInstance(boolean)
Starting with the documentation:
5 Answers
5
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How to check if an array field contains a unique value or another array in MongoDB?
I am using mongodb now.
2 Answers
2
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Center Align on a Absolutely Positioned Div
The div is at the top, but I can't center it with <center> or margin: 0 auto ;
9 Answers
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Why does “while(true)” without “Thread.sleep” cause 100% CPU usage on Linux but not on Windows?
I have created a simple program in java:
1 Answer
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