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Linear Regression and group by in R
...factor are your variables. Please keep in mind that Your.df must be a data.table class
– FraNut
Nov 17 '15 at 9:33
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How to concatenate columns in a Postgres SELECT?
I have two string columns a and b in a table foo .
8 Answers
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Laravel - Eloquent or Fluent random row
... This way you are retrieving all records and getting a random one. If your table has too many records this could be bad for your app.
– Anderson Silva
Jun 14 '16 at 14:23
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How should I choose an authentication library for CodeIgniter? [closed]
... set
Very good documentation
Simple and elegant database design (just 4 DB tables)
Most features are optional and easily configured
Language file support
reCAPTCHA supported
Hooks into CI's validation system
Activation emails
Login with email, username or both (configurable)
Unactivated accounts aut...
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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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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Looping through a hash, or using an array in PowerShell
I'm using this (simplified) chunk of code to extract a set of tables from SQL Server with BCP .
7 Answers
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Setting the MySQL root user password on OS X
... server in safe mode with privilege bypass
sudo mysqld_safe --skip-grant-tables;
In a new window connect to the database, set a new password and flush the permissions & quit:
mysql -u root
For MySQL older than MySQL 5.7 use:
UPDATE mysql.user SET Password=PASSWORD('your-password') WHERE ...
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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