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Efficiently updating database using SQLAlchemy ORM
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184
SQLAlchemy's ORM is meant to be used together with the SQL layer, not hide it. But you do have...
How do you run a command for each line of a file?
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137
Read a file line by line and execute commands: 4 answers
This is because there is not only 1 ...
How to run crontab job every week on Sunday
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10 Answers
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How to resolve symbolic links in a shell script
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19 Answers
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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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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 ...
Guards vs. if-then-else vs. cases in Haskell
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From a technical standpoint, all three versions are equivalent.
That being said, my rule of t...
SortedList, SortedDictionary and Dictionary
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When iterating over the elements in either of the two, the elements will be sorted. Not so wi...
iOS: How to get a proper Month name from a number?
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11 Answers
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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...