SAP Buffering

When accessing database tables using Open SQL, SAP buffering is effective as standard if it is activated for the corresponding database table. It can be explicitly deactivated using the addition BYPASSING BUFFER of the statement SELECT.

In addition to the explicit specification of BYPASSING BUFFER, SAP buffering can also be bypassed implicitly by some variants of the Open SQL statements, as the corresponding operation can only be executed in the database and not in the SAP buffer.

The following Open SQL statements implicitly bypass the SAP buffer and access the database tables directly:

• SELECT with the addition FOR UPDATE,

• Access to a table using single-record buffering without selecting a single record using SINGLE SELECT or by specifying the primary key in the WHERE condition (this behavior depends on the current implementation of the database interface and may be different in future releases).

• SELECT with the addition DISTINCT,

• SELECT with aggregate expressions,

• Open SQL statement with the addition CLIENT SPECIFIED, without specification of the client ID in a WHERE condition,

• SELECT with JOIN expressions

• Access to a generically buffered area without full specification in a WHERE condition

• Open SQL statements with IS [NOT] NULL in the additions WHERE and HAVING,

• Use of a subquery in a WHERE condition,

• SELECT with the addition GROUP BY,

• SELECT with the addition ORDER BY, whereby the sort key is not the primary key.

Note

Bypassing the SAP buffer with the above additions is a means to increase the performance when accessing buffered database tables. To explicitly bypass the SAP buffer in the SELECT statement, always use the addition BYPASSING BUFFER instead of the implicit behavior of the additions stated above.