java - Why does a Derby database take up so much space? -


i new databases , love how easy data relational database (such derby database). don't how data 1 takes up; have made database 2 tables, written total of 130 records these tables (each table has 6 columns), , whole relational database gets saved in system directory folder houses total of approximately 1914014 bytes! (assuming did arithmetic right....) heck going on cause such huge request of memory?! //i notice there log1.dat file in log folder takes 1mb of data. looked file via notepad++, , saw null characters. about?

when last checked in 2011, empty derby database takes 770 k of disk space: http://apache-database.10148.n7.nabble.com/database-size-larger-than-expected-td104630.html

the log1.dat file transaction log, , records database changes database can recovered if there crash (or if program calls rollback).

note log1.dat disk space, not memory.

if you'd learn basics of derby's transaction log, start here: http://db.apache.org/derby/papers/recovery.html


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