at selection-screen

[Former Member]

could anyone tell me the technical definitions and differences for select single and select upto 1 rows ??

and also while validating select single is used to validate the parameters and select upto 1 rows is used to validate the select-options ???

tell me clearly ..plezzzzzzzzzzzzzzzzz

[raguraman_c]

Hi,

check out this link. If not clear feel free to revert back.

http://www.sap-basis-abap.com/abap/difference-between-select-single-and-up-to-1-row.htm

--Ragu

[Former Member]

thanks raghu

[former_member181962]

1) select single expects the whole key to be passed.

select up to 1 rows doesn't .

2) select up to 1 rows will get the first of the available rows matching the condition. Select single also does the same ,but you would get an error when you do an EPC check for your program.

3) You have to use select up to 1 rows for validating select-options because, select options can result in multiple records and hence you will considered the entered value in the select-option to be valid, if it fetches even one valid record.

Even if you use select single for validating a select-option, it would result in a EPC error.

REgards,

ravi

[Former Member]

According to SAP Performance course the SELECT UP TO 1 ROWS is faster than SELECT SINGLE because you are not using all the primary key fields.

select single is a construct designed to read database records with primary key. In the absence of the primary key, it might end up doing a sequential search, whereas the select up to 1 rows may assume that there is no primary key supplied and will try to find most suitable index.

The best way to find out is through sql trace or runtime analysis.

Use "select up to 1 rows" only if you are sure that all the records returned will have the same value for the field(s) you are interested in. If not, you will be reading only the first record which matches the criteria, but may be the second or the third record has the value you are looking for.

The System test result showed that the variant Single * takes less time than Up to 1 rows as there is an additional level for COUNT STOP KEY for SELECT ENDSELECT UP TO 1 ROWS.

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.

Mainly: to read data from

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, applies any aggregate, ordering or grouping functions to them and then returns the first record of the result set.

Mainly: to check if entries exist.

Nagh samala, one request for you, If the answers are helping you to solve the query then you need to mark them and reward points.

Best Regards,

Vibha

*Please mark all the helpful answers

[Former Member]

thank u for ur answer

[Former Member]

thanks vibha

[Former Member]

Hi,

According to SAP Performance course the SELECT UP TO 1 ROWS is faster than SELECT SINGLE because you are not using all the primary key fields.

select single is a construct designed to read database records with primary key. In the absence of the primary key, it might end up doing a sequential search, whereas the select up to 1 rows may assume that there is no primary key supplied and will try to find most suitable index.

The best way to find out is through sql trace or runtime analysis.

Use "select up to 1 rows" only if you are sure that all the records returned will have the same value for the field(s) you are interested in. If not, you will be reading only the first record which matches the criteria, but may be the second or the third record has the value you are looking for.

The System test result showed that the variant Single * takes less time than Up to 1 rows as there is an additional level for COUNT STOP KEY for SELECT ENDSELECT UP TO 1 ROWS.

Regarding parameter & select-option there is no restriction for using select single.. or select...upto one row.

Regards,

Dharitree

[Former Member]

Select single doesnt need endselect. and is efficient.

select upto always reads all possible hits.so time consuming and less efficient. It needs endselect statement.

Coding without endselect statement helps u during debugging. It wont give a dump. If you use select-endselect statements, it might give u dump when trying to debug it.

Regards,

Sandeep Josyula

*Reward if helpful

[abdul_hakim]

hi

check the below link..

https://www.sdn.sap.com/irj/sdn/developerareas/abap?rid=/library/uuid/840ad679-0601-0010-cd8e-9989fd...

Cheers,

Abdul Hakim