The Query Optimizer tries to select best plan for any query and it does that based on generating all possible plans, estimating cost of them, and selects cheapest costed plan. Estimating cos…Full description
woodworking
StructureFull description
Include a Structure More Than Once in a Database Table
Periodic Table Tricks in bangla
col
Ejercicios de usando la base de datos Adventure WorksDescripción completa
Design with Singapore spec
Descripción: REWRWRWE
Steel Comp a Ration Table
Creation of a Table Pool and Pool Table
Table of specifications in Home economics
Descripción completa
Manual on using the Table of Specifications based on the Learning Competencies in 5th Grade Science. Attachment to the Competencies
Contents Introduction.......................................................................................................................................2 Using F1 option................…Descrição completa
java time table project for computer studentsFull description
EpidDeskripsi lengkap
CA CL_CI_TEST_SELECT_TA CL_CI_TEST_SELECT_TAW_BYBUF W_BYBUF 0001 Purpose of the Check Buffered table in a JOIN
JOINs bypass the SAP table buffer. Buffered tables should be accessed using the simplest SELECT statements possible so as not to risk bypassing the buffer. If one of the tables in a JOIN is buffered, it is best to first import the required entries using a SELECT into an internal table itab, and then (for example, using the statement SELECT ... FOR ALL ENTRIES IN itab) access the further tables. This naturally applies only if the buffered table can be accessed using the SAP table buffer . Click the link to find out what you can do. This message can be hidden using t he pseudo comment "#EC CI_BUFFJOIN SELECT statements that bypass the S AP table buffer
ABAP Coding TIP You should proceed as follows whenever a SELECT statement on a buffered table bypasses the SAP table buffer. Note that changes in the buffering settings can also affect other statements. The size of the SAP table buffers is limited; some large tables with incorrect buffering settings can displace many small tables from the buffer.
If the statement (form routine, function module, method, program, ...) is part of customizing, customizing, check whether an explicit BYPASSING BUFFER should be added to the SELECT statement.Perhaps the buffer was bypassed intentionally and this was specified implicitly until now. The set of statements that bypass the buffer can however change in future development. If a bypass is wanted, this should be formulated explicitly. If not, select the SELECT statement with the required pseudo comment "#EC CI_....
If the statement is used frequently in the production system, system, try to reformulate the WHERE condition so that the SAP table buffer can be used. Likewise, it can be of benefit to replace ABAP JOINs containing buffered tables by SELECT statements in the individual tables. Even the SELECT additions DISTINCT and ORDER BY (the latter means that the buffer is bypassed if the sort order does not match the primary key) can be processed faster in buffered tables using ABAP methods. This naturally applies only if the SELECT statement can use the SAP table buffer on the basis of the WHERE condition.
Only as a last resort should resort should you think of changing the buffering settings. Use the where-used list to examine how the table is accessed in different ways. Perhaps the table should be buffered differently (for example, using single-record buffering instead of generically) or not at all.
Purpose of the Check SELECT statements that bypass the S AP table buffer
When reading data, SAP table buffering (the buffering of database tables on the application server) has a major performance advantage over accessing the database. Buffer, therefore, any suitable tables and do not bypass the buffer for buffered tables. The following can produce a bypass:
Bypassing by design using SELECT ... FOR UPDATE and SELECT ... BYPASSING BUFFER
Use in JOINs
Use in subqueries
Aggregate functions COUNT, MAX, MIN, SUM, AVG
SELECT DISTINCT ...
... GROUP BY ...
... ORDER BY ... if the sort fields have a different order than in the primary key
... IS [NOT] NULL in the WHERE condition
(Generic) key not specified in full when using generic or single record buffering
Key not specified in full when using CLIENT SPECIFIED on a client-specific table without a client field in the WHERE condition
What do I do if a SELECT statement bypasses the SAP table buffer? This check does not report the bypassing of the table buffer when using Native SQL well as when using constructs such as SELECT * FROM dbtab AS db WHERE db~field1 > db~field2. From SAP_BASIS 7.10, the keyword SINGLE is no longer necessary for (buffer) access to a single record buffered table.
