PARALLELWRITE= Table Option

Determines whether SPD Server uses parallel processing to write data in HDFS.

Valid in:	SPD Server
Valid in:	DATA step and PROC step
Default:	0, which means no parallel processing for Write operations.
Interactions:	The PARALLELWRITE= table option setting overrides the SPDSHPWR= macro variable setting. For more information, see SPDSHPWR= Macro Variable.
Interactions:	When parallel Write processing occurs, the order in which the rows are written is unpredictable. The order in which the rows are returned cannot be determined unless the application imposes ordering criteria.
See:	Parallel Processing for Data in HDFS

Syntax

Required Argument

Example

Syntax

PARALLELWRITE=threads

Required Argument

threads

specifies the number of threads to use for Write operations. Specifying 1 thread is the same as the default 0, which means no parallel processing for Write operations.

Interaction	The SPD Server MAXWHTHREADS= parameter file option, which is specified in the spdsserv.parm parameter file, determines the maximum number of threads that SPD Server uses for parallel processing. For more information, see the MAXWHTHREADS= parameter file option in the SAS Scalable Performance Data Server: Administrator’s Guide.
Note	Negative numbers are invalid and will result in an error.

Example

libname class sasspds 'mydomain' server=myhost.5400 user="anonymous";

proc append base=class.StudentID data=class.Ages (parallelwrite=8); 
run;

Note: Because SPD Server must be enabled to operate in select Hadoop environments, you might want to determine whether a libref is in a Hadoop domain. For example, to determine whether the libref Class is in a Hadoop domain, submit the LIBNAME LIST statement libname class list;. If the queried libref is in a Hadoop domain, SPD Server returns HADOOP=YES.