DBMS_SNAPSHOT

The DBMS_SNAPSHOT package provides a programmatic interface through which you can manage snapshots and purge snapshot logs. For detailed information about snapshots (read-only copies of tables), see Chapter 16 in the Oracle7 Server Administrator Guide.

The DROP_SNAPSHOT procedure

This procedures drops the specified snapshot. The specification is:

PROCEDURE DBMS_SNAPSHOT.DROP_SNAPSHOT (mowner VARCHAR2, master VARCHAR2, snapshot DATE);

The GET_LOG_AGE procedure

This procedures gets the oldest date entry in the log. The specification is:

PROCEDURE DBMS_SNAPSHOT.GET_LOG_AGE (oldest IN OUT date, mow VARCHAR2, mas VARCHAR2);

The PURGE_LOG procedure

This procedure purges the specified log of any unnecessary rows. The specifications are:

PROCEDURE DBMS_SNAPSHOT.PURGE_LOG (master VARCHAR2, num NUMBER); PROCEDURE DBMS_SNAPSHOT.PURGE_LOG (master VARCHAR2, num NUMBER, flag VARCHAR2);

The REFRESH procedure

This procedure causes a manual refresh of the snapshot. The procedure is overloaded so that you can specify an optional refresh option. The specifications are:

PROCEDURE DBMS_SNAPSHOT.REFRESH (snapshot VARCHAR2); PROCEDURE DBMS_SNAPSHOT.REFRESH (snapshot VARCHAR2, op VARCHAR2);

The REFRESH_ALL procedure

This procedure causes a refresh of all snapshots waiting to be refreshed automatically. The specification is:

PROCEDURE DBMS_SNAPSHOT.REFRESH_ALL;

The SET_UP procedure

This procedure prepares the specified master site to refresh a snapshot. The specification is:

PROCEDURE DBMS_SNAPSHOT.SET_UP (mowner VARCHAR2, master VARCHAR2, log IN OUT VARCHAR2, snapshot IN OUT date, snaptime IN OUT date);

The WRAP_UP procedure

The WRAP_UP procedure records a refresh at the master site. The specification is:

PROCEDURE DBMS_SNAPSHOT.WRAP_UP (mowner VARCHAR2, master VARCHAR2, sshot DATE, stime DATE);