I have some Z small tables, for which i am activating Buffering.
1. I have taken the premesaurement from ST05(by running the report where the table is used in select query)
2. After that i have activated the buffer for those tables.
3. Then i ran the required reports /FM .
4. Then after sometime, i tried to take ST05 trace by running the report again. But in ST05 Sql trace i am not able to see the Z tables .
Could you please help why the ztables not displayed in after it is buffered...
I can imagine 2 possibilities:
- either you didn't tick the checkbox for buffered tables in ST05 (that's a different checkbox than other database tables)
- or your program uses Open SQL statements that skip the buffer (like for SELECT : ORDER BY, BYPASSING BUFFER, etc. -> [SAP Library: Buffering Database Tables|http://help.sap.com/saphelp_nw70/helpdata/en/cf/21f244446011d189700000e8322d00/frameset.htm ])
A third one maybe (I'm not sure, I let other people confirm): If I remember well, there can also be the possibility that the SAP buffer for buffered tables is not large enough and there is swap (ST02 transaction), and the table is not used enough to be kept in the buffer.
> 4. Then after sometime, i tried to take ST05 trace by running the report again. But in ST05 Sql trace i am not able to see the Z tables .
well that's how it is supposed to be, isn't it? After buffering they are processed in the table buffer and you can't see them in the sql trace (done by the DBI) anymore. Only in the buffer trace (blue lines) you can see them (if they are processed by the buffer)
the name of the performance trace are no really accurate.
Open SQL statements can be processed by the database or by the table buffer (if buffering is switched on and statement can make use of it and buffer is filled)
the SQL trace (by default activated) is actually the database trace, it shows the statements going to the database and use the yellow background color.
the buffer trace (usually not activated) shows the SQL statements going to the table buffer and use blue background color.