The SYSCOLSTAT system view contains the column statistics, including histograms, that are used by the optimizer. The contents of this view are best retrieved using the sa_get_histogram stored procedure or the Histogram utility. The underlying system table for this view is ISYSCOLSTAT.
| Column name | Data type | Description |
|---|---|---|
| table_id | UNSIGNED INT | A number that uniquely identifies the table or materialized view to which the column belongs. |
| column_id | UNSIGNED INT | A number that, together with table_id, uniquely identifies the column. |
| format_id | SMALLINT | For system use only. |
| update_time | TIMESTAMP | The time of the last update of the column statistics. |
| density | FLOAT | An estimate of the average selectivity of a single value for the column, not counting the large single value selectivities stored in the row. |
| max_steps | SMALLINT | For system use only. |
| actual_steps | SMALLINT | For system use only. |
| step_values | LONG BINARY | For system use only. |
| frequencies | LONG BINARY | For system use only. |
For databases created using SQL Anywhere 12, the underlying system table for this view is always encrypted to protect the data from unauthorized access.
Constraints on underlying system table |
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