Adaptive Server stores transaction names in a column of varchar(255) (as compared to varchar(64) in previous server versions) to accommodate the length and format of transaction names supplied by different distributed transaction protocols. In the X/Open XA protocol, for instance, distributed transactions are assigned a transaction name consisting of both a global transaction ID (gtrid) and a branch qualifier. Within Adaptive Server, this information is combined in the xactname column of the systransactions table.
systransactions.xactname stores the names of both externally-created distributed transactions (defined by an X/Open XA transaction manager or MSDTC) and local server transactions. Clients defining local transactions can name those transactions anything they wish, within the confines of the varchar(255) column. Similarly, external transaction managers can use a variety of different formats to name a distributed transaction.
