Amit v$ views are documented by Oracle, whereas x$ fixed tables are not. So, if programs are written accessing these objects & expect those programs to work across versions then v$views should be preferred. v$ views are simply externalizing data from x$ fixed tables and not all information from x$ tables are externalized. Of course, v$fixed_view_definition and v$fixed_table can be used. v$fixed_table.type will tell whether a v$/x$ object is view or fixed table. v$fixed_view_definition will has v$/gv$ view definition. HTH Thanks Riyaj The Pythian Group On Tue, Apr 22, 2008 at 7:04 PM, 조동욱 <ukja.dion@xxxxxxxxx> wrote: > v$fixed_view_definition would be a good start point. > Also check gv$ views which expose global-version of v$views. > > Dion Cho > > 2008/4/23, Amit Verma <in.amitverma@xxxxxxxxx>: > > > Dear All, > > http://forums.oracle.com/forums/forum.jspa?forumID=61 > > > > 1. Where we can use X_$ or V_$. > > 2. Is X_$ and V_$ contains the same data/info. > > If the info is not same, then at which the info is presented. > > 3. Is both X_$ and V_$ are views > > > > Please let me know your concerns. > > > > Thanks, > > Amit Verma > > Oracle DBA & System Adminstrator > > > > E-Mail:- in.amitverma@xxxxxxxxx, v.amit@xxxxxxxxxxx > > WebSite:- http://www.linkedin.com/in/vamit > > IM:- verma.labs@xxxxxxxxx > > Mobile:- (+91) 98910.98927 > > > > > >