Set Connection (QxdaSetConnection) API

A transaction manager calls QxdaSetConnection() to perform XA-transaction related operations for a particular connection.

Authorities and Locks

None.

Required Parameter Group

Connection handle

INPUT; BINARY(4)

The handle number of the connection on which to perform the XA operation. The connection handle must have been generated by the QxdaConnectEDRS API in the current job and activation group.

Transaction branch identifier

INPUT; CHAR(*)

The transaction branch identifier. This identifier is generated by the transaction manager when it starts the transaction branch. The max length is 140 bytes.

Offset		Type	Field
Dec	Hex
0	0	BINARY(4)	Format identifier
4	4	BINARY(4)	Length of global transaction identifier
8	8	BINARY(4)	Length of branch qualifier
12	C	CHAR(128)	Data field

Format identifier:	Identifies the naming format being used. If OSI CCR naming is used, the format identifier should be set to 0. If some other format is used, a the value should be greater than 0. A value of -1 means the transaction branch identifier is null.
Length of global transaction identifier:	Identifies the first of at most two contiguous components comprised by the data field. This specifies the number of bytes (1-64) starting at the first byte of the data element. This is not null-terminated.
Length of branch qualifier:	Identifies the second of at most two contiguous components comprised by the data field. This specifies the number of bytes (1-64) starting at the first byte after the global transaction identifier. This is not null-terminated.
Data field:	Contains the data of the transaction branch identifier.

Return value

OUTPUT; BINARY(4)

The return value of the XA operation. Possible return values:

-8	[XAER_DUPID]	The xid already exists.
-7	[XAER_RMFAIL]	An error occurred that makes the resource manager unavailable.
-6	[XAER_PROTO]	The operation was not successful. Function was called in an improper context.
-5	[XAER_INVAL]	The operation was not successful. Incorrect arguments were specified.
-4	[XAER_NOTA]	The specified xid is not known by the resource manager.
-3	[XAER_RMERR]	The operation was not successful. An unexpected error occurred.
-2	[XAER_ASYNC]	The operation was not successful. The resource manager does not support asynchronous operations.
0	[XA_OK]	The operation was successful.

Operation

INPUT; BINARY(4)

Valid operations are:

QXDA_SQL_TXN_FIND:	(1)	Allows a connection to attach to an existing transaction branch.
QXDA_SQL_TXN_CREATE:	(2)	Creates a new transaction branch.
QXDA_SQL_TXN_SUSPEND:	(3)	Disassociates the connection from the transaction branch and only closes the native files (end with suspend). The SQL cursors remain open so the same connection can pick up the transaction branch and continue where it left off.
QXDA_SQL_TXN_END:	(4)	Disassociates the connection from the transaction branch (no suspend).
QXDA_SQL_TXN_END_FAIL:	(5)	Disassociates the connection from the transaction branch (no suspend) and marks it as rollback only.
QXDA_SQL_TXN_RESUME:	(6)	Resumes a suspended transaction branch.
QXDA_SQL_TXN_LOOSELY_ COUPLED_CREATE:	(7)	Creates a new transaction branch that shares locks with other loosely coupled transaction branches.
QXDA_SQL_TXN_JOIN:	(8)	Allows a connection to join to an existing transaction branch.

Note:QXDA_SQL_TXN_JOIN, QXDA_SQL_TXN_CREATE, QXDA_SQL_TXN_LOOSELY_COUPLED_CREATE, and QXDA_SQL_TXN_RESUME are similar to a xa_start; whereas, QXDA_SQL_TXN_SUSPEND, QXDA_SQL_TXN_END, and QXDA_SQL_TXN_END_FAIL are similar to a xa_end.

Note:QXDA_SQL_TXN_FIND has the same result as a QXDA_SQL_TXN_JOIN.

Timeout value

INPUT; BINARY(4)

Timeout value for the transaction in seconds. If the Timout Value is not greater than 0, then the default system timeout value will be used. This value must be >= 0 and applies to the QXDA_SQL_TXN_CREATE and QXDA_SQL_TXN_LOOSELY_COUPLED_CREATE operations.

Error code

I/O; CHAR(*)

The structure in which to return error information. For the format of the structure, see Error Code Parameter.

Usage Notes

This function may be called from the initial thread of a job only.

Error Messages

Related Information

The QxdaXA APIs follow the NTS (transactions with transaction scoped locks) model. For more information regarding the NTS model, see XA APIs.

Example

See Code disclaimer information for information pertaining to code examples.

#include qxdaedrs.h 

main()
{ 
err_t     err; 
Qxda_CDBI0100_t *istr = (Qxda_CDBI0100_t *)instruct;
Qxda_CDBO0100_t  ostr;
int ostrsize;
XID inxid;
char gtrid[8] = "TestXA";
char bqual[6] = "Test"; 
inxid.formatID = 0;  
inxid.gtrid_length = 6; 
inxid.bqual_length = 4; 
int create = QXDA_SQL_TXN_CREATE;
int timeoutval = 60;
int ret_val; 
_CPYBYTES(dtaara, gtrid, inxid.gtrid_length); 
_CPYBYTES(dtaara + inxid.gtrid_length, bqual, inxid.bqual_length);   
_CPYBYTES(inxid.data, dtaara, inxid.gtrid_length + inxid.bqual_length); 
XID *xid = &inxid;





 memset(istr, '\0', sizeof(Qxda_CDBI0100_t));                  

 istr->Connection_Type = 'U';                                                        
 memset(istr->Server_Name, ' ', 256);                  
 istr->Commitment_Control = 'S';                          
 _CPYBYTES(istr->Commit_Scope, "*XA                      ", 10);         
 istr->Allow_Suspend = 'Y';
 memset(istr->RDB_Specified, '0', 1);
 istr->SQLDA_Cache_Size = 10;                             
 istr->Offset_Job_Data = sizeof(Qxda_CDBI0100_t);         
 istr->Length_Job_Data = 7;                               
 _CPYBYTES((char *)istr + istr->Offset_Job_Data, "CONNECT", 7);   
 istr->Offset_Suspend_Data = istr->Offset_Job_Data + istr->Length_Job_Data; 
 istr->Length_Suspend_Data = 7;   
 memset(istr->RDB_Name, ' ', 18);
 _CPYBYTES(istr->TM_Info, "TM_Name         ", 10); 
 istr->LockTimeoutVal = 10;  
 ostrsize = sizeof(Qxda_CDBO0100_t);                                        


 QxdaConnectEDRS(istr, "CDBI0100", &ostr, &ostrsize,
                  "CDBO0100", &err);


 QxdaSetConnection(&ostr.Connection_Handle,  xid, &ret_val, &create, &timeoutval, &err);
}