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ASP.NET PDF Viewer using C#, VB/NETBefore Oracle Database 10g, executing a DROP TABLE command would result in the immediate removal of the table and all its dependent objects, and all of the related space in that table segment would be released back to the database. In Oracle Database 10g, however, the table and dependent objects aren t immediately removed. They are renamed, but they temporarily stay in the same location, and Oracle will retain them for as long as possible, based on space pressure. As noted earlier, these dropped objects are listed in the Recycle Bin, which is simply a logical container (a data dictionary table that maintains information about dropped tables, such as their new and original names). You can query it as you would a normal table to view its contents with a simple SELECT * FROM RECYCLEBIN command. As long as a table is still listed in the Recycle Bin, it can be restored at any time using the Flashback Drop feature. any size barcode generator in excel free to download, barcode in excel free, active barcode excel 2010 download, how to barcode in excel 2010, free 2d barcode generator excel, barcode in excel 2003 erstellen, barcode generator macro excel, barcode generator excel mac, barcode plugin excel 2007, how to add barcode font to excel 2007,inflow.meeddy.com, info.meeddy.com, inform.meeddy.com, know.meeddy.com, refine.meeddy.com, stack.meeddy.com, what.meeddy.com, simple.meeddy.com, quick.meeddy.com, annotate.meeddy.com,comment.meeddy.com,drawing.meeddy.com,link.meeddy.com,bookmark.meeddy.com,attach.meeddy.com,upload.meeddy.com,download.meeddy.com,property.meeddy.com,thumb.meeddy.com,outline.meeddy.com,search.meeddy.com,jump.meeddy.com,rotate.meeddy.com,pan.meeddy.com,hand.meeddy.com,arrow.meeddy.com,zoom.meeddy.com,highlight.meeddy.com,underline.meeddy.com, Analogous to the #import extension, C++/CLI comes with the #using directive to reference .NET assemblies. The following code references the assembly System.dll via a #using directive: // referencingAssemblies1.cpp // compile with "cl /clr:safe referencingAssemblies1.cpp" #using <System.dll> using namespace System; int main() { // System::Uri is defined in the assembly System.dll Uri^ uri = gcnew Uri("http://www.heege.net"); Console::WriteLine(uri->Host); // output: "www.heege.net" } This sample uses the type System::Uri, which is defined in the assembly System.dll. Without the #using directive, the compiler would complain that an undefined type System::Uri is used. To use the type System::Console, no #using directive is necessary. System::Console is defined in a very special assembly called mscorlib.dll. It defines many core types like System::Object, and even the types for the managed primitives. Therefore, mscorlib is automatically referenced by the C++/CLI compiler. There is no mandatory relationship between an assembly name and the name of the namespace in which the assembly s types are defined. As an example, System.dll and mscorlib.dll define types in the namespace System. If you re using make files or the new MSBUILD tool, or if you re building simple test solutions from a command shell, you can also set assembly references via the /FU commandline switch, as follows: // referencingAssemblies2.cpp // compile with "cl /clr:safe /FUSystem.dll referencingAssemblies2.cpp" // no need for #using <System.dll> using namespace System; int main() { Uri^ uri = gcnew System::Uri("http://www.heege.net"); Console::WriteLine(uri->Host); // output: "www.heege.net" } In Oracle Database 10g Release 2, you can use the RECYCLEBIN initialization parameter to turn the Tip Flashback Drop capability off. By default, the parameter is set to ON, which means that all dropped tables go into the Recycle Bin and you can recover them using the Flashback Drop feature. By setting the parameter s value to OFF, you turn the Flashback Drop feature off, and tables won t go into the Recycle Bin upon being dropped. #!/bin/sh old_stty_settings=$(stty -g) # Save original settings. stty -icanon theta=0 velocity=0 distance= height= time= A query on the DBA_FREE_SPACE view will tell you that the space previously occupied by these dropped objects is now free. In fact, however, this space is not immediately reclaimable by the database it is potential free space that is reclaimed later, once the objects have been removed for good. So, despite what the DBA_FREE_SPACE view tells you, these objects will continue to take up their original space allocation in their tablespaces until they are permanently deleted from the Recycle Bin. This deletion can occur in the following circumstances: A user can permanently remove the objects from the Recycle Bin using the PURGE command (DROP TABLE table_name PURGE). Oracle automatically removes the dropped objects in the Recycle Bin due to space pressure when Oracle doesn t have enough available free space in a tablespace to create a new object or to extend more space to an existing object. The Flashback Drop feature is automatically enabled in an Oracle Database 10g database. You don t have to configure a thing in order to use the feature. In summary, on issuing a DROP TABLE (or DROP INDEX) command in Oracle Database 10g, the objects in question are not truly dropped. Oracle simply hides them, and you can restore them at a later point using Flashback Drop. If you truly do want to permanently remove an object, you can use the PURGE option with the DROP command: SQL> DROP TABLE test PURGE; Let s take a look at all this in a bit more detail.
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