A data partition is an independent database object with a unique partition ID. It is a subset of a table, and shares the column definitions and referential and integrity constraints of the base table. To maximize I/O parallelism, Sybase recommends that you bind each partition to a different segment, and bind each segment to a different storage device.
Each semantically partitioned table has a partition key that determines how individual data rows are distributed to different partitions. The partition key may consist of a single partition key column or multiple key columns. The values in the key columns determine the actual partition distribution.
Range- and hash-partitioned tables can have as many as 31 key columns in the partition key. List partitions can have one key column in the partition key. Round-robin partitioned tables do not have a partition key.
You can specify partitioning-key columns of any type except:
text, image, and unitext
bit
Java classes
Computed columns
You can partition tables containing columns of these datatypes, but the partitioning key columns must be of supported datatypes.
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