Data Set Options for Relational Databases |
Specifies during SAS/ACCESS
read operations whether Teradata waits to acquire a lock or fails your request
when a different user has locked the DBMS resource.
Default value: |
LIBNAME setting
|
Valid in: |
DATA and PROC steps (when accessing DBMS data
using SAS/ACCESS software)
|
DBMS support: |
Teradata
|
-
YES
-
specifies that Teradata waits to acquire
the lock, and SAS/ACCESS waits indefinitely
until it can acquire the lock.
-
NO
-
specifies that Teradata fails the lock request
if the specified DBMS resource is locked.
If you specify READ_MODE_WAIT=NO, and
a different user holds a restrictive lock, then the executing
SAS step fails. SAS/ACCESS continues
to process the job by executing the next step. If you specify READ_MODE_WAIT=YES, SAS/ACCESS waits
indefinitely until it can acquire the lock.
A restrictive lock means that another user
is holding a lock that prevents you from obtaining your desired lock. Until
the other user releases the restrictive lock, you cannot obtain your lock.
For example, another user's table-level WRITE lock prevents you from obtaining
a READ lock on the table.
For more information, see locking topic in the Teradata
section.
To assign this option to a group of relational
DBMS tables or views, see the
READ_MODE_WAIT= LIBNAME Option.
Locking in the Teradata Interface
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