When importing a table, the export file is read and the table and data are created in the following order: 1 New tables are created. A key point is that these are technically NEW tables to the Oracle server. They have the same data and characteristics as the original tables, but in reality they are being newly created in the database. The reason that you cannot apply archive logs to roll forward an import is that there is no synchronizing information stored in either the logs or the export to specify when to start applying archived logs. 2 Index structures are built. The DBA can save some time during the import process by setting the parameter INDEXES=N, then building the indexes following the Import process. This will also limit the number of rollback segments required to support the import. 3 Data is automatically imported in the tables because the parameter ROWS is set to Y by default. Indexes are automatically populated because the parameter INDEXES is set to Y by default. Indexes are created along with the table and hence updated along with data import. 4 Triggers are imported and integrity constraints are enabled on new tables.The order in which you import tables may be important if you do not import all the objects that a user owns. For, example, if the table with the foreign key has a referential check on the table with the primary key, and the foreign key table is imported first, then all rows that reference the primary key that have not been imported will be rejected if the constraints were enabled. For a full database export this is not a problem.
in the following order:
1 New tables are created. A key point is that these are technically NEW tables
to the Oracle server. They have the same data and characteristics as the
original tables, but in reality they are being newly created in the database.
The reason that you cannot apply archive logs to roll forward an import is
that there is no synchronizing information stored in either the logs or the
export to specify when to start applying archived logs.
2 Index structures are built. The DBA can save some time during the import
process by setting the parameter INDEXES=N, then building the indexes
following the Import process. This will also limit the number of rollback
segments required to support the import.
3 Data is automatically imported in the tables because the parameter ROWS is
set to Y by default. Indexes are automatically populated because the
parameter INDEXES is set to Y by default. Indexes are created along with
the table and hence updated along with data import.
4 Triggers are imported and integrity constraints are enabled on new tables.The order in which you import tables may be important if you do not import all the
objects that a user owns. For, example, if the table with the foreign key has a
referential check on the table with the primary key, and the foreign key table is
imported first, then all rows that reference the primary key that have not been
imported will be rejected if the constraints were enabled. For a full database export this is not a problem.
llm06什么意思?english学的不好
有什么设置吗?