hello,
I thinking how can I use index statistics to optimize my DB.
I want know what does mean nodes total dup and max dup and if/how they
relation
for example, take this table and index below:

SAIDAPRODUTOS (161)
Primary pointer page: 265, Index root page: 266
Data pages: 178, data page slots: 178, average fill: 80%
Fill distribution:
0 - 19% = 5
20 - 39% = 3
40 - 59% = 1
60 - 79% = 79
80 - 99% = 90

Index RDB$PRIMARY30 (0)
Depth: 2, leaf buckets: 11, nodes: 8865
Average data length: 1.01, total dup: 0, max dup: 0
Fill distribution:
0 - 19% = 0
20 - 39% = 0
40 - 59% = 0
60 - 79% = 0
80 - 99% = 11

Index SAIDAPRODUTOS_IDX1 (1)
Depth: 2, leaf buckets: 10, nodes: 8865
Average data length: 0.30, total dup: 6266, max dup: 38
Fill distribution:
0 - 19% = 0
20 - 39% = 1
40 - 59% = 0
60 - 79% = 0
80 - 99% = 9

Index SAIDAPRODUTOS_IDX2 (2)
Depth: 2, leaf buckets: 9, nodes: 8865
Average data length: 0.02, total dup: 8740, max dup: 156
Fill distribution:
0 - 19% = 0
20 - 39% = 0
40 - 59% = 0
60 - 79% = 1
80 - 99% = 8

Index SAIDAPRODUTOS_IDX3 (3)
Depth: 2, leaf buckets: 15, nodes: 8865
Average data length: 0.38, total dup: 5886, max dup: 107
Fill distribution:
0 - 19% = 0
20 - 39% = 0
40 - 59% = 8
60 - 79% = 4
80 - 99% = 3

SAIDAPRODUTOS_IDX1, SAIDAPRODUTOS_IDX2 and SAIDAPRODUTOS_IDX3 are in
columns many used in WHERE clauses.
theres any doc about this index stats?

TIA