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List All Redis Databases
...atabases is fixed, and set in the configuration file. By default, you have 16 databases. Each database is identified by a number (not a name).
You can use the following command to know the number of databases:
CONFIG GET databases
1) "databases"
2) "16"
You can use the following command to list ...
Efficiently updating database using SQLAlchemy ORM
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SQLAlchemy's ORM is meant to be used together with the SQL layer, not hide it. But you do have...
Iterate a list with indexes in Python
...ar I've seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
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SVN undo delete before commit
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svn revert deletedDirectory
Here's the documentation for the svn revert command.
EDIT
If dele...
Can I query MongoDB ObjectId by date?
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12 Answers
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Get number of digits with JavaScript
...d like to know how many digits var number has. For example: If number = 15; my function should return 2 . Currently, it looks like this:
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Creating an R dataframe row-by-row
...code in R.
If you can, allocate your entire data.frame up front:
N <- 1e4 # total number of rows to preallocate--possibly an overestimate
DF <- data.frame(num=rep(NA, N), txt=rep("", N), # as many cols as you need
stringsAsFactors=FALSE) # you don't know levels y...
Linux command (like cat) to read a specified quantity of characters
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194
head works too:
head -c 100 file # returns the first 100 bytes in the file
..will extract ...
How do I check that a number is float or integer?
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It is more efficient to use if-return-return or if-else-return?
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Since the return statement terminates the execution of the current function, the two forms are e...