Should columns only be read once....

Good day,
I have a question about reading the resultset.
I was recently reading the java.sql API.
And in the description for the Resultset interface.
It mentions that "each column should be read only once"     
Currently I don't call columns via results.getString("column") directly.
I usually set it to a variable and the use the variable as much as i need.
This method mainly helps me keep organized.
I was wondering if there are any real problems or issues that may arise from calling a column directly a numerous amount of times.
I don't plan on chaning my current method of going about resultsets, but i was just curious.
thanks,
alex

Hi,
You can scroll through the result set and read a column any number of time (provided proper resultSetType is set during statement creation).
see the scenario where such things will not work (but depends on the driver implementation). suppose u are retrieving rows in bulk (say >10k number of rows of large size).retrieving the bulk will give u out of memory etc exceptions. and if u set the fetchsize(int size)method things will become ok. but here u cant gurantee that u will get the column value on ur second visit to the same column (ie calling rs.getXX()method second time) .
so the rule thumb is retrieve the column value only once and store it in a variable- this is what u are doing rt now (if its a large value, process it on the spot according to ur need)
HTH,
-asharafkk

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