Oracle Application Server 10.1.3.4, Руководство пользователя

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Metadata for the IMS/DB Data Source
A-10 Oracle Application Server Adapters for IMS/DB User's Guide
Use the Indexes group box to specify cardinality for the columns in each of the indexes
in the table:
Generating Statistics
Click Update in the Statistics tab to generate updated statistics for the table. The
Update Statistics screen is displayed, as shown in the following figure:
Figure A–5 The Update Statistics screen
The following tables list the fields that are used to update statistics:
Use the Type group to specify the following:
Cardinality The number of distinct values for the column. If the value
is
-1
, then the number of distinct values for the column is
unknown (a value was not supplied and the update
statistics utility was not run to update the value). A value
of
0
indicates that there are no distinct values for the
column.
Table A–9 Indexes group Components
Field Description
Indexes and
segments The indexes and segments in the table.
Cardinality The number of distinct key values in the index. If the value
is
-1
, then the number of distinct key values in the index
is unknown (a value was not supplied and the update
statistics utility was not run to update the value). A value
of
0
indicates that there are no distinct key values in the
index.
Table A–8 (Cont.) Columns group Components
Field Description