Difference between select single and up to 1 row
by rmsb on Tuesday, April 21st, 2009 | No Comments
The ‘SELECT SINGLE’ statement selects the first row in the database that it finds that fulfils the ‘WHERE’ clause If this results in multiple records then only the first one will be returned and therefore may not be unique.
The ‘SELECT ….*….. UP TO 1 ROWS’ statement is subtly different. The database selects all of the relevant records that are defined by the WHERE clause or lack of, applies any aggregate, ordering or grouping functions to them and then returns the first record of the resultant result set.
Samples:
*
Select single Posnr
from vbrp
into w_POSNR.
*
Select Posnr
into table t_internal
from VBRK
up to 1 rows
order by Posnr descending.
