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BC430 ABAP Dictionary. Unit 8 Search Help 、 Unit 7 Views. 1. Search Help. Input Help Requirements. Search Help. 決定由哪個 table 或 view 找資料. (2). (1). Search Help. Selection Method of a Search Help. Description of the Dialog Behavior. Interface of a Search Help. IMPORT (IMP) :
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BC430ABAP Dictionary Unit 8 Search Help 、Unit 7 Views
Search Help 決定由哪個table或 view 找資料 (2) (1)
IMPORT (IMP): screen上的值會作為一個限制條件,加入到 search help中 EXPORT (EXP): 哪些欄位需要 返回值 Search Help
search help 可放至 1. Tablefield 2. check table 3. data element Search Help
1 若有好幾個search help,由左而右決定優先順序 2 3 Search Help
2. Collective search help: 把幾個 elementary search help 組合在一起 Search Help
(1) Join Condition 多餘的欄位
Data Selection with Views • You would get the same result using an Inner Join: SELECT C~CARRID C~CARRNAME P~CONNID P~CITYFROM P~CITYTO F~FLDATE F~SEATSMAX F~SEATSOCC INTO TABLE ITAB_FLIGHTS FROM ( SCARR AS C INNER JOIN SPFLI AS P ON C~CARRID = P~CARRID ) INNER JOIN SFLIGHT AS F ON F~CARRID = P~CARRID AND F~CONNID = P~CONNID WHERE CITYFROM IN SO_CITYF AND CITYTO IN SO_CITYT AND SEATSOCC < F~SEATSMAX ORDER BY C~CARRID P~CONNID F~FLDATE.
The Different Types and Usage of Views • Database View • are implement an inner join • that is, only records of the primary table (selected via the join operation) for which the corresponding records of the secondary tables also exist are fetched. • Maintenance View • are implement an outer join • Data from several tables can be summarized in a maintenance view and maintained collectively via this view. • That is, the data is entered via the view and then distributed to the underlying tables by the system.
Dynamic attachment of table fields in database views • You can include entire tables in database views. • In this case all the fields of the included table become fields of the view. • If new fields are included in the table or existing fields are deleted, the view is automatically adjusted to this change. • A new or deleted field is therefore automatically included in the view or deleted from it.
2.2 Maintenance Views • Data that is distributed on more than one table often forms a logical unit (application object) • The user usually is not interested in the technical implementation, such as the distribution of the data on several tables. • You should be able to display, change and create the data of such an application object together. • You can maintain complex application objects in a simple way using a maintenance view. • The data is automatically distributed on the underlying database tables.