RDB$INDEX_SEGMENTS
RDB$INDEX_SEGMENTS
stores the segments (table columns) of indexes and their positions in the key.A separate row is stored for each column in an index.
Column Name | Data Type | Description |
---|---|---|
|
|
The name of the index this segment is related to.The master record is |
|
|
The name of a column belonging to the index, corresponding to an identifier for the table and that column in |
|
|
The column position in the index.Positions are numbered left-to-right, starting at zero |
|
|
The last known (calculated) selectivity of this column in the index.The higher the number, the lower the selectivity. |