The LIBNAME Statement for Relational Databases

REREAD_EXPOSURE= LIBNAME Option

Specifies whether the SAS/ACCESS engine functions like a random access engine for the scope of the LIBNAME statement.

Default value:	NO
Valid in:	SAS/ACCESS LIBNAME statement
DBMS support:	Aster nCluster, DB2 under UNIX and PC Hosts, DB2 under z/OS, Greenplum, HP Neoview, Informix, Microsoft SQL Server, MySQL, Netezza, ODBC, OLE DB, Oracle, Sybase, Sybase IQ, Teradata

Syntax
Syntax Description
Details
See Also

Syntax

REREAD_EXPOSURE=YES | NO

Syntax Description

NO: specifies that the SAS/ACCESS engine functions as an RMOD engine, which means that your data is protected by the normal data protection that SAS provides.
YES: specifies that the SAS/ACCESS engine functions like a random access engine when rereading a row so that you cannot guarantee that the same row is returned. For example, if you read row 5 and someone else deletes it, then the next time you read row 5, you read a different row. You have the potential for data integrity exposures within the scope of your SAS session.

Details

CAUTION:: Using REREAD_EXPOSURE= could cause data integrity exposures.

HP Neoview, Netezza, ODBC, and OLE DB: To avoid data integrity problems, it is advisable to set UPDATE_ISOLATION_LEVEL=S (serializable) if you set REREAD_EXPOSURE=YES.

Oracle: To avoid data integrity problems, it is advisable to set UPDATE_LOCK_TYPE=TABLE if you set REREAD_EXPOSURE=YES.