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How do I interactively unstage a particular hunk in git?
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3 Answers
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Active
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Rails: How to list database tables/objects using the Rails console?
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308
You are probably seeking:
ActiveRecord::Base.connection.tables
and
ActiveRecord::Base.conn...
How to drop into REPL (Read, Eval, Print, Loop) from Python code
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answered Sep 8 '09 at 20:34
AlexAlex
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PHP foreach loop key value
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393
You can access your array keys like so:
foreach ($array as $key => $value)
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How to change the CHARACTER SET (and COLLATION) throughout a database?
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371
change database collation:
ALTER DATABASE <database_name> CHARACTER SET utf8 COLLATE utf...
Delete element in a slice
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edited Oct 14 '18 at 10:23
flornquake
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answered J...
Replace all 0 values to NA
...me space for it. E.g.,
data.frame(x = c(1, NA, 2))
# x
# 1 1
# 2 NA
# 3 2
Also, the data frame structure requires all the columns to have the same number of elements so that there can be no "holes" (i.e., NULL values).
Now you could replace zeroes by NULL in a data frame in the sense of com...