java - About resultset type JDBC -


in this oracle java tutorial, says:

type_forward_only: result set cannot scrolled; cursor moves forward only, before first row after last row. rows contained in result set depend on how underlying database generates results. is, contains rows satisfy query @ either time query executed or rows retrieved.

"the rows contained in result set depend on how underlying database generates results."

what's difference between query execution time , rows retrieving time? , how can know database supports? in advance.

it's difference between eager , lazy loading. i'd recommend researching terms.

eager loading means results made available @ once. require great deal of time , memory if set large.

lazy loading doles out results needed. it's along lines of google when search pages: they'll find millions, return them 25 @ time higher ranks first.


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