LogMiner Data Dictionary
The dbms_capture_adm.build procedure
extracts data dictionary information to the redo log. The
extracted data dictionary information in the redo log is
consistent with the primary data dictionary at the time when the
dbms_capture_adm.build procedure is run. The build
procedure is automatically run when the Capture process is
created.
The amount of information extracted to a
redo log, when the dbms_capture_adm.build procedure is
run, depends on the number of database objects in the database.
The dbms_capture_adm.build procedure generates a
corresponding valid first SCN value that can be specified when
the new Capture process is created. A First SCN generated by the
dbms_capture_adm.build procedure can be found by running
the following query:
SELECT DISTINCT FIRST_CHANGE#, NAME FROM
V$ARCHIVED_LOG WHERE DICTIONARY_BEGIN = 'YES';
Propagation and Apply processes use a
Streams data dictionary to keep track of the database objects
from a particular source database. A Streams data dictionary is
populated whenever one or more database objects are prepared for
instantiation at a source database. When a database object is
prepared for instantiation, it is recorded in the redo log. When
a Capture process scans the redo log, it uses this information
to populate the local Streams data dictionary for the source
database. After an object has been prepared for instantiation,
the local Streams data dictionary is updated whenever a DDL
statement on the object is processed by a Capture Process.
