I have a requirement to perform an action against a subset of rows in a DB2 table, i.e. not all rows, but only those that match a WHERE clause. The requirement is to retrieve all of the rows that match the WHERE clause, but in a "random" order. I am thinking I can use a statement like the following

DECLARE RANDOM_CURSOR FOR

SELECT rand() as idx, <and other columns)

WHERE ...

ORDER BY idx 

Will this work?

And do I have to SELECT rand(), and if so, what is its datatype?

This might work for you, for the data type RAND return floating point, https://www.ibm.com/docs/en/db2-for-zos/13.0.0?topic=functions-random-rand 

SELECT NAME FROM (                        
SELECT RAND(),NAME FROM SYSIBM.SYSTABLES  
WHERE CREATOR ='SYSIBM'                   
ORDER BY 1        )                       
---------+---------+---------+---------+--
NAME                                      
---------+---------+---------+---------+--
SYSVIEWDEP_H                              
SYSDBAUTH                                 
SYSPACKAUTH_H                             
SYSCHECKS                                 
SYSCOLUMNS                                
DB2_SYSPARM                               
SYSINDEXPART                              
SQTCOLUMNS_OLEDB                          
SYSROUTINEAUTH                            
SYSCONTROLS_RTXT                          
SYSVARIABLEAUTH                           
SYSROUTINES_OPTS                          

I have a requirement to perform an action against a subset of rows in a DB2 table, i.e. not all rows, but only those that match a WHERE clause. The requirement is to retrieve all of the rows that match the WHERE clause, but in a "random" order. I am thinking I can use a statement like the following

DECLARE RANDOM_CURSOR FOR

SELECT rand() as idx, <and other columns)

WHERE ...

ORDER BY idx 

Will this work?

And do I have to SELECT rand(), and if so, what is its datatype?

I have a requirement to perform an action against a subset of rows in a DB2 table, i.e. not all rows, but only those that match a WHERE clause. The requirement is to retrieve all of the rows that match the WHERE clause, but in a "random" order. I am thinking I can use a statement like the following

DECLARE RANDOM_CURSOR FOR

SELECT rand() as idx, <and other columns)

WHERE ...

ORDER BY idx 

Will this work?

And do I have to SELECT rand(), and if so, what is its datatype?