IBM FileNet P8, Version 5.2

Column-length limitations for generated-column database indexes for class properties (DB2 for Linux, UNIX and Windows)

Column-length limitations can be exceeded when you create generated-column indexes for object store databases. These limitations apply if the object store database is a DB2® for Linux, UNIX and Windows database. You receive an error if you exceed these limitations.

The error message is as follows:

SQL0614N The index or index extension "I_GENEV" cannot be created or altered because the combined length of the specified columns is too long. SQLSTATE=54008

Column-length limitations can be easily exceeded because of the differing maximum number of characters for a generated column versus a non-generated column. Here are the details:

Byte maximum for a column	The maximum number of bytes for a database column is 8 KB. (This maximum is a consequence of the Content Platform Engine page size of 32 KB.)
Character maximum for a non-generated column	For string data, the data type of a non-generated column is Vargraphic. This data type requires 2 bytes of storage per character. Thus, to avoid exceeding the 8 KB limit, the maximum number of characters for a Vargraphic column is 4000.
Character maximum for a generated column	A generated column such as `LOWER(column-name)` returns the Varchar data type. This data type requires 3 bytes of storage per character. Thus, if `column-name` is a Vargraphic column with a maximum of 4000 characters, the generated column requires 12000 bytes of storage. This amount of storage exceeds the 8 KB limit.