OPEN And Native SQL

What is open sql Vs native sql?

Open SQL – These statements are a subset of standard SQL. It consists of DML command (Select, Insert, Update, Delete). It can simplify and speed up database access. Buffering is partly stored in the working memory and shared memory. Data in buffer is not always up to date.

Native SQL – They are loosely integrated into ABAP. It allows accessing all functions containing programming interface. They are not checked and converted. They are sent directly to the database system. Programs that use Native SQL are specific to the database system for which they were written. For e.g. to create or change table definition in the ABAP.

In the 'select' statement what is 'group by'?

Group by clause is used to fetch the data from the table by the specified field.

What will you use SELECT SINGLE or SELECT UPTO 1 ROWS?

It is particularly important for us to understand the difference between SELECT SINGLE and SELECT UP TO 1 ROWS... We use select single when we need to get one record form data base table with where condition, we should pass key field in where condition.
We use SELECT UP TO 1 ROWS to get a single record from data base table where there is no key field at our side.
In simple SELECT SINGLE is used to get exact record from data base whereas SELECT UP TO 1 ROWS is use to get approximate record from data base.

What is the function of using the insert statement in SAP ABAP?

The insert statement helps in the adding of a record at a certain specified location.

What is Asynchronous and Synchronous update?

Asynchronous Update – The program does not wait for the work process to finish the update. Commit Work.
Synchronous Update – The program waits for the work process to finish the update. Commit Work and Wait.

What does an exec Sql Stmt do in ABAP? What is the disadvantage of using it?

To use a Native SQL statement, we must precede it with the EXEC SQL statement, and follow it with the ENDEXEC statement as follows -

EXEC SQL [PERFORMING <form>].
<Native SQL statement>
ENDEXEC.

There is no period after Native SQL statements. Furthermore, using inverted commas (") or an asterisk (*) at the beginning of a line in a native SQL statement does not introduce a comment as it would in normal ABAP syntax. We need to know whether table and field names are case-sensitive in your chosen database.