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Spring @Transactional - isolation, propagation
...e exists.
Isolation
Defines the data contract between transactions.
Read Uncommitted: Allows dirty reads.
Read Committed: Does not allow dirty reads.
Repeatable Read: If a row is read twice in the same transaction, the result will always be the same.
Serializable: Performs all transactions in...
Android read text raw resource file
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What if you use a character-based BufferedReader instead of byte-based InputStream?
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String line = reader.readLine();
while (line != null) { ... }
Don't forget that readLine() skips the...
Optimistic vs. Pessimistic locking
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Optimistic Locking is a strategy where you read a record, take note of a version number (other methods to do this involve dates, timestamps or checksums/hashes) and check that the version hasn't changed before you write the record back. When you write the record back...
Specifying colClasses in the read.csv
I am trying to specify the colClasses options in the read.csv function in R. In my data, the first column "time" is basically a character vector while the rest of the columns are numeric.
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Get pandas.read_csv to read empty values as empty string instead of nan
I'm using the pandas library to read in some CSV data. In my data, certain columns contain strings. The string "nan" is a possible value, as is an empty string. I managed to get pandas to read "nan" as a string, but I can't figure out how to get it not to read an empty value as NaN. Here's sam...
A variable modified inside a while loop is not remembered
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echo -e $lines | while read line
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done
The while loop is executed in a subshell. So any changes you do to the variable will not be available once the subshell exits.
Instead you can use a here string to re-write the while loop to be in t...
How to read a file into a variable in shell?
I want to read a file and save it in variable, but I need to keep the variable and not just print out the file.
How can I do this? I have written this script but it isn't quite what I needed:
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Why do I need Transaction in Hibernate for read-only operations?
Why do I need Transaction in Hibernate for read-only operations?
4 Answers
4
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What is the difference between Non-Repeatable Read and Phantom Read?
What is the difference between non-repeatable read and phantom read?
9 Answers
9
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What is the difference between Reader and InputStream?
What is the difference between Reader and InputStream?
And when to use what?
If I can use Reader for reading characters why I will use inputstream, I guess to read objects?
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