todo

oracle引用库

From version 0.3.2 i've splitted the TODO list into two parts
of that should be done before release 1.0.0 and what could be done later

Here's what should be done first
- Support for RETURNING clause
- Support for global transactions
- add describe functionality

This features should be added before release 2.0.0
- Support for Oracle Objects
- Support for external procedures 
- Support for Qracle AQ

+ make distribution canonical (Partly done for version 0.4.1)
+ Support for nested tables. Done in version 0.3.2
+ Support for ref cursors. Done in version 0.3.1
+ Add abstract class OraType, and make it parent of all types.
  types are string,number,lob,date. done in Version 0.3.0
+ Add BLOB/CLOB support done in version 0.2.0
+ Add transactions done in version 0.1.0
+ Make OraError more intelegent add "ocicpplib" types of errors done in Version 0.0.3

+ add "hash row" feature (let programmer obtain a col val by name) done in Version 0.0.3

+ work more carefully with number done in Version 0.0.2

* use piecewice operations for varchar2 long long raw deceased in Version 0.3.1
	Because of there's no need to use long columns so it seems there's no need for 
	piecewice operations because basic structures let me fetch varchar LOB's and REF's 
	Hope it enough at the moment.


Some bugs to be fixed..
null pointer exception
You can get a NULL pointer exception in ~Cursor if
bind fails. What happens is that bind does:
binds[par] = 0;
... OCIBindByName(stmthp, &(binds[par]), ...
The OCIBindByName fills in a handle value in the binds
map. However if OCIBindByName fails binds[par] gets
left as NULL.

~Cursor calls Cusrsor::drop, which does:
map<string,OCIBind *>::const_iterator ci=binds.begin();
while(ci!=binds.end()) {
OCIHandleFree(ci->second,OCI_HTYPE_BIND);
*ci++;
DEBUG(DLEV_DEBUG,"Bind nandle freed\n");
}

ci->second may be NULL. The siumple fix is to replace
this code with:
map<string,OCIBind *>::const_iterator ci=binds.begin();
while(ci!=binds.end()) {
OCIBind* pBind = ci->second;
if(pBind != NULL) {
OCIHandleFree(pBind,OCI_HTYPE_BIND);
}
*ci++;
DEBUG(DLEV_DEBUG,"Bind nandle freed\n");
} 


 When I compiled the source with Microsoft VC++, there are 
 some errors. If you would like and have time and have no 
 impact on other operating system(I have tested in G++), 
 modify them please in next version.
 1. In Function declare and Function implement, there are 
 many places where the defalt values are set. 
 MODIFY: default value only set in function declare.
 2. OCILobRead: 
 In Declare(ociap.h) is: long (__cdecl *)(void *,const 
 void *,unsigned long,unsigned char);
 while used in ocicpplib: long (__cdecl *)(void *,void 
 *,unsigned long,unsigned char)
 MODIFY: second parameter: void* -> const void*