pg_prepared_xacts
   The view pg_prepared_xacts displays
   information about transactions that are currently prepared for two-phase
   commit (see PREPARE TRANSACTION for details).
  
   pg_prepared_xacts contains one row per prepared
   transaction.  An entry is removed when the transaction is committed or
   rolled back.
  
Table 51.78. pg_prepared_xacts Columns
| Column Type Description | 
|---|
| 
        Numeric transaction identifier of the prepared transaction | 
| 
        Global transaction identifier that was assigned to the transaction | 
| 
        Time at which the transaction was prepared for commit | 
| 
        Name of the user that executed the transaction | 
| 
        Name of the database in which the transaction was executed | 
   When the pg_prepared_xacts view is accessed, the
   internal transaction manager data structures are momentarily locked, and
   a copy is made for the view to display.  This ensures that the
   view produces a consistent set of results, while not blocking
   normal operations longer than necessary.  Nonetheless
   there could be some impact on database performance if this view is
   frequently accessed.