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 Table ID 

The database user  specifies a table by entering its name. The table is accessed internally using a table ID of a fixed length.

The relationship between the table name and this table ID is stored in the database catalog.

In addition, the database system has a special management structure (file directory), in which the root pages of B* trees are assigned to table IDs.

The table IDs are stored in the file directory together with a type flag and other information. The type flag specifies whether the table contains primary data, secondary key , or LONG data. The type flag specification enables one table ID to be used for all the B* trees required for the logical structures of the same table.

 

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