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PostgreSQL: Difference between text and varchar (character varying)
What's the difference between the text data type and the character varying ( varchar ) data types?
9 Answers
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SQL Server : Columns to Rows
...icatorname, indicatorvalue);
Finally, if you have 150 columns to unpivot and you don't want to hard-code the entire query, then you could generate the sql statement using dynamic SQL:
DECLARE @colsUnpivot AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX)
select @colsUnpivot
= stuff((select ','+qu...
How can I check if a program exists from a Bash script?
... validate that a program exists, in a way that will either return an error and exit, or continue with the script?
37 Answer...
Saving and loading objects and using pickle
I´m trying to save and load objects using pickle module.
First I declare my objects:
7 Answers
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Difference between volatile and synchronized in Java
... am wondering at the difference between declaring a variable as volatile and always accessing the variable in a synchronized(this) block in Java?
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Environment variables for java installation
...A_TOOL_OPTIONS with value -Dfile.encoding="UTF-8". This ensures that Java (and tools such as Maven) will run with a Charset.defaultCharset() of UTF-8 (instead of the default Windows-1252). This has saved a lot of headaches when wirking with my own code and that of others, which unfortunately often a...
Listing all permutations of a string/integer
...from my experience of interviews though) is to take a string or an integer and list every possible permutation.
28 Answers
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Switch statement for greater-than/less-than
...going to put them in a comment but I thought it was better to benchmark it and share the results. You can test it yourself. Below are my results (ymmv) normalized after the fastest operation in each browser (multiply the 1.0 time with the normalized value to get the absolute time in ms).
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What's the difference between emulation and simulation? [duplicate]
In simple understandable terms, what is the difference between the two terms?
10 Answers
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Convert nested Python dict to object?
...nt way to get data using attribute access on a dict with some nested dicts and lists (i.e. javascript-style object syntax).
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