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Difference between local and global indexes in DynamoDB
... table. When you query records via the local index, the operation consumes read capacity units from the table. When you perform a write operation (create, update, delete) in a table that has a local index, there will be two write operations, one for the table another for the index. Both operations w...
Removing index column in pandas when reading a csv
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When reading to and from your CSV file include the argument index=False so for example:
df.to_csv(filename, index=False)
and to read from the csv
df.read_csv(filename, index=False)
This should prevent the issue so you don...
How to append output to the end of a text file
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To append a file use >>
echo "hello world" >> read.txt
cat read.txt
echo "hello siva" >> read.txt
cat read.txt
then the output should be
hello world # from 1st echo command
hello world # from 2nd echo command
hello siva
To overwrite a file use ...
Difference between HBase and Hadoop/HDFS
...FS allows you store huge amounts of data in a distributed (provides faster read/write access) and redundant (provides better availability) manner. And MapReduce allows you to process this huge data in a distributed and parallel manner. But MapReduce is not limited to just HDFS. Being a FS, HDFS lack...
How to read and write excel file
I want to read and write an Excel file from Java with 3 columns and N rows, printing one string in each cell. Can anyone give me simple code snippet for this? Do I need to use any external lib or does Java have built-in support for it?
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In Bash, how to add “Are you sure [Y/n]” to any command or alias?
...Hamish's answer. They handle any mixture of upper and lower case letters:
read -r -p "Are you sure? [y/N] " response
case "$response" in
[yY][eE][sS]|[yY])
do_something
;;
*)
do_something_else
;;
esac
Or, for Bash >= version 3.2:
read -r -p "Are you su...
Timeout for python requests.get entire response
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That is not for the entire response. requests.readthedocs.org/en/latest/user/quickstart/#timeouts
– Kiarash
Feb 23 '14 at 17:38
1
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What is “with (nolock)” in SQL Server?
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WITH (NOLOCK) is the equivalent of using READ UNCOMMITED as a transaction isolation level. So, you stand the risk of reading an uncommitted row that is subsequently rolled back, i.e. data that never made it into the database. So, while it can prevent reads being dea...
How to read lines of a file in Ruby
I was trying to use the following code to read lines from a file. But when reading a file , the contents are all in one line:
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Change SQLite database mode to read-write
How can I change an SQLite database from read-only to read-write?
14 Answers
14
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