Indexes, like tables, can be partitioned. Prior to Adaptive Server 15.0, all indexes were global. With Adaptive Server 15.0, you can create local as well as global indexes.
An index partition is an independent database object identified with a unique combination of index ID and partition ID; it is a subset of an index, and resides on a segment or other storage device.
Adaptive Server supports local and global indexes.
A local index – spans data in exactly one data partition. For semantically partitioned tables, a local index has partitions that are equipartitioned with their base table; that is, the table and index share the same partitioning key and partitioning type.
For all partitioned tables with local indexes, each local index partition has one and only one corresponding data partition.
A global index – spans all data partitions in a table. Sybase supports only unpartitioned global indexes. All unpartitioned indexes on unpartitioned tables are global.
You can mix partitioned and unpartitioned indexes with partitioned tables:
A partitioned table can have partitioned and unpartitioned indexes.
An unpartitioned table can have only unpartitioned, global indexes.
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