select x,y,z from 3,4,5 tables

I use a view.

Hi David,

your WHERE clause contains
relationship infos (c.id = d.id,b.some_id = c.some_id,a.other_id = b.other_id)
some hardcoded (b.x in (1,2,3) and b.y > 0)
as well as single SEARCH( a.id = pn_id)

in uniface, you can use some kind of filter mechanism.
We paint all the entities A,B,C.D next to each other
and a dummy entity where we can store the results with the fields col_a, col_b and col_d

We start with the select on entity A set
id.a = pn_id
and do a retrieve/e "A"

for each occurence in A we select in B:
clear/e "B"
other_id.b = other_id.a
y.b = "> 0" ; <GOLD>>
x.b = "1|2|3" ; <GOLD>|
retrieve/e "B"

for each occurence in B, we select in C
clear/e "C"
some_id.c = some_id.b
retrieve/e "C"

for each occurence in C, we select in D
clear/e "D"
id.d = id.c
retrieve/e "D"

for each hit, in D, we fill our dummy entity
col_a.dummy = col.a
col_b.dummy = col.b
col_d.dummy = col.d


But there is an easier way to do in uniface:
**********************************
If you have defined relationships between A, B, C and D in the model
And you paint entity B inside of A, C inside of B and D inside of C
Then uniface will take care fetching the related many entities.

To solve the hardcoded "b.x in (1,2,3) and b.y > 0"
we put in the <READ> trigger of entity B a U_WHERE clause

read u_where (y > 0 & (x = 1 | X = 2 | X=3) )

Sucecss, Uli

P.S for the u_where the help-info reads as
The SelectionCriteria consists of one or more relational phrases with the operands linked by relational operators (<, !=, and so on) connected by logical operators (&, |, and so on).

Remember that possible profile characters are always stripped from the SelectionCriteria, with the exception of "*" and "?", which are treated as literals. For example:

read u_where (NAME = "A|B")

results in the following SelectionCriteria:

NAME = "AB"




> -----Ursprüngliche Nachricht-----
> Von: "dammie" <MusilDavid@seznam.cz>
> Gesendet: 13.07.09 23:39:56
> An: uniface-l@uug.org
> Betreff: [Uniface-L] select x,y,z from 3,4,5 tables


> Hello,
>
> do you have any muster that you use if you have rewrite select in uniface:
>
> e.g.
>
> select a.col, b.col, d.col from a t1, b t2, c t3, d t4
> where c.id = d.id
> b.some_id = c.some_id
> b.x in (1,2,3) and b.y > 0
> a.other_id = b.other_id
> a.id = pn_id
>
> do you use nested loops or do you use read where clausule or do you simply use stored procedure and return entity to uniface?
>
> Thanks for your views on topic
>
> David
> _______________________________________________
> Uniface User Group Discussion Forum
> For more information: http://lists.umanitoba.ca/mailman/listinfo/uniface-l
> To unsubscribe/set options: http://lists.umanitoba.ca/mailman/options/uniface-l
>

-- Ulrich Merkel --
ulrichmerkel@web.de
+49(69)317881
_______________________________________________
Uniface User Group Discussion Forum
For more information: http://lists.umanitoba.ca/mailman/listinfo/uniface-l
To unsubscribe/set options: http://lists.umanitoba.ca/mailman/options/uniface-l

 

Many thanks for your hints...

David