rdbms - what exactly the undo information lives in oracle? -


some docs says, there "undo tablespaces" implies should create tablespace undo imformation.

some docs says, there "undo segment" implies undo information lives in normal tablespaces , use of it's segment.

so, undo information lives , organized?

earlier releases of oracle database used rollback segments store undo. oracle9i introduced automatic undo management, simplifies undo space management eliminating complexities associated rollback segment management. oracle recommends (oracle 9i , on words) use undo tablespace (automatic undo management) manage undo rather rollback segments.

when creating undo tablespace, these automatically created:

n undo segments (based on sessions parameter value) named _syssmun$ owned public (usable ops configuration) not manually manageable


Comments

Post a Comment

Popular posts from this blog

javascript - RequestAnimationFrame not working when exiting fullscreen switching space on Safari -

request animation frame stops working when exiting fullscreen clicking on original space's safari window. fine if fullscreen mode canceled escape key or calling cancelfullscreen(). steps reproduce: open https://dl.dropboxusercontent.com/u/769042/prezi/safari-fullscreen.html click "draw raf", kittie appears click "fullscreen", go fullscreen click "draw raf", kittie appears go space original safari was, showing "click exit fullscreen mode", click anywhere, out fullscreen click "draw raf", nothing happens what handling click calling: window.requestanimationframe(draw); which draws on canvas context: function draw() { ctx.drawimage(img, math.random()*500|0, math.random()*400|0, 100, 100); } i checked .hidden , .visibilitystate, updated correctly. tested on osx 10.9.3, safari 7.0.4 (9537.76.4). has workaround/solution other switching old settimeout? this sounds webkit bug 88940 : using reque
Read more

Python ctypes access violation with const pointer arguments -

i have api i'm trying wrap in python (2.7.6 on win7) code using ctypes. here's api: client_dllfunc bool clientapi search_exporttoclipcopy(clienthsearch handle, int channel, lpctstr filename, const time_t& from, const time_t& to, const bool* cameras, int length, bool usepassword, lpctstr password, bool includetextin = false, bool excludeplayer = false); the issue i'm having cameras argument; , i've had issue other const pointer arguments well. here's how i'm wrapping api: def search_exporttoclipcopy(self, hsearch, csearch, filename, tfrom, tto, cameras, length, usepassword, password, includetextin=true, excludeplayer=false): exporttoclipcopy = self.sdkdll.search_exporttoclipcopy exporttoclipcopy.argtypes = [c_int, c_int, c_wchar_p, c_long, c_long, pointer(c_bool), c_int, c_bool, c_wchar_p, c_bool, c_bool] exporttoclipcopy.restype = c_bool exporttoclipcopy(hsearch, csearch, filename, tfrom, tto, cameras, length, usepassword, pass
Read more