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SAS/SHARE User's Guide


This option specifies the level at which shared update access to a SAS data set is denied. A SAS data set can be opened concurrently by more than one SAS session or by more than one statement, window, or procedure within a single session. For example, with the FSEDIT procedure you can request two windows for the same SAS data set in one session. You can use only one of the following arguments with the CNTLLEV= data set option:

specifies that concurrent access is controlled at the SAS data set (or member) level. Member-level control restricts concurrent access to only one update access but allows read access to many sessions, procedures, or statements.

specifies that concurrent access is controlled at the observation (or record) level. Record-level control allows more than one update access to the same SAS data set but denies concurrent update of the same observation. If you use CNTLLEV=REC, you can access the same SAS data set with two FSEDIT windows.

By default, SAS procedures permit the greatest degree of concurrent access possible while guaranteeing the integrity of the data and the data analysis. Some statements and commands require member-level control and ignore the CNTLLEV= option. See SAS Language Reference: Dictionary for more information about this option.


set datalib.fuel (cntllev=rec) point=obsnum;

set datalib.fuel (cntllev=mem);
by area;

The first SET statement changes the control level from the default of member to the record level by specifying the CNTLLEV= option. The second SET statement changes the control level from record to the member level. This might be done to ensure that a data set does not change while you are processing it. See Changing the Data Set Option Default Object for more information.

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