Compaq AA-Q88CE-TE manual Microsoft DTC Support, XA Support Introduction, Modified RTR API

XA Support

C.1 Introduction

facility_name = user-specified facility name /resource_manager = the name of those RMs this facility references

For example:

CREATE FACILITY test /front=N1 /back=N2/router=N3 /resource_manager=(employ_rm,payroll_rm)

C.1.3 Modified RTR API

An application written to use RTR with XA does not need all existing RTR application programming interface statements. In particular, there is no longer a need to include code to handle rtr_mt_msg1_uncertain messages.

C.1.4 RTR Open Channel

RTR relies on the server application to specify which RM it is attached to using the open channel API. The server must submit an RM instance name with open string to the RTR open channel API before accessing the desired database. Both the RM instance name and the database name (RM name) contained in open string must be the same as that registered earlier using the REGISTER RM command. This information is now stored in the RTR key segment structure. A new RTR_F_OPE_XA_MANAGED flag is created to associate the channel with the XA interface. For example:

typedef struct {

rtr_keyseg_type_t ks_type; [RM_NAME_TYPE]

rtr_keylen_t	ks_length;	[N/A]
rtr_keylen_t	ks_offset;	[N/A]
rtr_pointer_t	ks_lo_bound; [RM_NAME]
rtr_pointer_t	ks_hi_bound;	[OPEN_STRING]

} rtr_keyseg_t;

C.2 Microsoft DTC Support

RTR for Windows NT is interoperable with Microsoft's Distributed Transaction Controller (DTC). DTC is supported via the RTR XA software architecture. That is, with the X/Open XA protocol, RTR users can develop application programs to update MS SQL Server databases, MSMQ, or other Microsoft resource managers under the control of a true distributed transaction.

This is possible because RTR (as a distributed transaction manager) is able to directly communicate with MS DTC to manage a transaction or perform a recovery via the XA protocol. For each standard XA call received from RTR, MS DTC will translate it into a corresponding OLE transaction call that SQL Server or MSMQ can use to update databases.

C–2XA Support