Release 10.1A: OpenEdge Data Management:
SQL Development

> ## Updating index statistics

> The `UPDATE STATISTICS` command uses the following syntax:

> Syntax
>     UPDATE ( [ TABLE | INDEX | [ ALL ] COLUMN ] STATISTICS [ AND ] ) ...
>     [ FOR table_name ]

> The following example demonstrates the use of the `UPDATE STATISTICS` statement for a single table:

>     UPDATE INDEX STATISTICS FOR Employee;

> The following example updates statistics for indexes and columns for a single employee:

>     UPDATE TABLE STATISTICS AND INDEX STATISTICS
>     AND COLUMN STATISTICS FOR Employee ;

> To create the new index statistics for all tables in a database, simply use the statement shown in Example 10–3.

> Example 10–3: UPDATE INDEX STATISTICS statement
>     UPDATE INDEX STATISTICS ;

> Notes: To create the new index statistics, SQL makes one pass over each index, reading every index entry and counting unique values. This is usually a CPU-intensive operation. When a table has many indexes, this operation can take quite a bit more time than the default `UPDATE STATISTICS`.
> `UPDATE STATISTICS` does not lock user data. It only locks the output statistics rows (and also acquires a shared lock on the schema). This means that user-level transactions can freely run concurrently with `UPDATE STATISTICS`.

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