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How big can a user agent string get?
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My take on this:
Use a dedicated table to store only UserAgents (normalize it)
In your related tables, store an Foreign Key value to point back to the UserAgent auto-increment primary key field
Store the actual UserAgent string in a TEXT field and care not a...
JPA - Returning an auto generated id after persist()
... Its not working giving zero as a Return after persisting the data into table. either refresh is not working at this case .. What should i do for this. please suggest a way... Thank you
– Vikrant Kashyap
Jun 13 '16 at 6:57
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How do you run a single query through mysql from the command line?
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mysql -u <user> -p -e "select * from schema.table"
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Is storing a delimited list in a database column really that bad?
...m in a comma separated list of values stored in one column of the database table.
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How can an html element fill out 100% of the remaining screen height, using css only?
... is where magic comes into picture - since we have 'min-height' on playing table, we are telling browser that <body> is superior over <html> because <body> holds the min-height. This in turn, allows <body> to override <html> because <html> had height already earli...
UITableView + Add content offset at top
I need to add some blank space to the top of my UITableView that does not affect the size of the content area. Shifting the content down or adding a blank cell is NOT what I want to do. Instead I just want an offset.
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Rails migrations: self.up and self.down versus change
... you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation the methods currently supported from the change method).
But pay attention becaus...
How do I replace NA values with zeros in an R dataframe?
...the complete results.
If you are struggling with massive dataframes, data.table is the fastest option of all: 40% faster than the standard Base R approach. It also modifies the data in place, effectively allowing you to work with nearly twice as much of the data at once.
A clustering of other he...
Tricks to manage the available memory in an R session
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I use the data.table package. With its := operator you can :
Add columns by reference
Modify subsets of existing columns by reference, and by group by reference
Delete columns by reference
None of these operations copy the (potentially...
Django dump data for a single model?
...Django dumpdata management command allows you to dump data from individual tables:
./manage.py dumpdata myapp1 myapp2.my_model
You can also separate multiple apps and models on the command line. Here's the canonical definition:
django-admin dumpdata [app_label[.ModelName] [app_label[.ModelName] ...