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Re: Why Clusters do not support LOBs [message #90837 is a reply to message #90836] |
Mon, 14 February 2005 07:50 |
Nagadeep
Messages: 12 Registered: October 2002
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Junior Member |
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Use the CREATE CLUSTER statement to create a cluster. A cluster is a schema object that contains data from one or more tables, all of which have one or more columns in common. Oracle stores together all the rows (from all the tables) that share the same cluster key.
The CLUSTER clause indicates that the table is to be part of cluster. The columns listed in this clause are the table columns that correspond to the cluster's columns. Generally, the cluster columns of a table are the column or columns that make up its primary key or a portion of its primary key.
Specify one column from the table for each column in the cluster key. The columns are matched by position, not by name.
A clustered table uses the cluster's space allocation. Therefore, do not use the PCTFREE, PCTUSED, INITRANS, or MAXTRANS parameters, the TABLESPACE clause, or the storage_clause with the CLUSTER clause.
Object tables and tables containing LOB columns cannot be part of a cluster.
You cannot specify CLUSTER with either ROWDEPENDENCIES or NOROWDEPENDENCIES unless the cluster has been created with the same ROWDEPENDENCIES or NOROWDEPENDENCIES setting.
Regards,
Nagadeep@Oracle
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