driver table in select for all entries

[Former Member]

anyone please let me what is driver table in select for all entries and when do we go for select for all entries

[Former Member]

hi Ganesh,

When there is huge data mainatained in your database you will make use of select for all entries statement instead of using joins ... but what is driver table that you are reffering here ???

Regards,

Santosh

[suresh_datti]

If we have an itab with some entries & would like to select entries from a database tablee that have matching fields in the itab. We use FOR ALL ENTRIES in such a scenario to avoid opening the itab loop. It helps in reducing runtime.. The itab is the driver table here.

~Suresh

[Former Member]

Here is something from help

FOR ALL ENTRIES WHERE

Syntax

... FOR ALL ENTRIES IN itab WHERE ... col operator itab-comp ...

Effect

If the addition FOR ALL ENTRIES is specified before the language element WHERE, then the components comp of the internal table itab can be used as operands when comparing with relational operators.

The internal table itab must have a structured line type and the component comp must be compatible with the column col.

The logical expression sql_cond of the WHERE condition can comprise various logical expressions by using AND and OR. However, if FOR ALL ENTRIES is specified, there must be at least one Comparison with a column of the internal table itab, which can be specified either statistically or dynamically (Release 6.40 and higher). In a statement with a SELECTstatement with FOR ALL ENTRIES, the addition ORDER BY can only be used with the addition PRIMARY KEY.

The whole logical expression sql_cond is evaluated for each individual line of the internal table itab. The resulting set of the SELECT statement is the union of the resulting sets from the individual evaluations. Duplicate lines are automatically removed from the resulting set. If the internal table itab is empty, the whole WHERE statement is ignored and all lines in the database are put in the resulting set.

Notes

In Release 6.10 and higher, the same internal table can be specified after FOR ALL ENTRIES and after INTO.

The addition FOR ALL ENTRIES is only possible before WHERE conditions of the SELECT statement.

Example

Exporting all flight data for a specified departure city. The relevant airlines and flight numbers are first put in an internal table entry_tab, which is evaluated in the WHERE condition of the subsquent SELECT statement.

PARAMETERS p_city TYPE spfli-cityfrom. 

TYPES: BEGIN OF entry_tab_type, 
         carrid TYPE spfli-carrid, 
         connid TYPE spfli-connid, 
       END OF entry_tab_type. 

DATA: entry_tab   TYPE TABLE OF entry_tab_type, 
      sflight_tab TYPE SORTED TABLE OF sflight 
                       WITH UNIQUE KEY carrid connid fldate. 

SELECT carrid connid 
       FROM spfli 
       INTO CORRESPONDING FIELDS OF TABLE entry_tab 
       WHERE cityfrom = p_city. 

SELECT carrid connid fldate 
       FROM sflight 
       INTO CORRESPONDING FIELDS OF TABLE sflight_tab 
       FOR ALL ENTRIES IN entry_tab 
       WHERE carrid = entry_tab-carrid AND 
             connid = entry_tab-connid. 

Regards,

Santosh