回复 7# wangzk0206 http://www-01.ibm.com/support/kn ... c/doc/c0052331.html"Table-level compression dictionary creationTable-level compression dictionaries for tables that you enable for adaptive or classic row compression can be built automatically ...
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Table-level compression dictionary creation
Table-level compression dictionaries for tables that you enable for adaptive or classic row compression can be built automatically or manually. Tables that you enable for adaptive compression include page-level data dictionaries, which are always automatically created.
Automatic dictionary creation
Starting with DB2® Version 9.5, a table-level compression dictionary is created automatically if each of the following conditions is met:
You set the COMPRESS attribute for the table by using the CREATE TABLE or ALTER TABLE statement with the COMPRESS YES ADAPTIVE or COMPRESS YES STATIC clause.
A table-level compression dictionary does not already exist for the table.
The table contains sufficient data for constructing a dictionary of repeated data.
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