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 or later, 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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