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Propietati de tip array in tabelele din Windows Azure (part 2)

Partea 1 http://vunvulearadu.blogspot.com/2011/02/propietati-de-tip-vector-in-tabele-din.html
Continuare:
In ultimul meu post am descris trei variante prin care se poate persista o entitate care contine o propietate de tip array( lista) intr-un tabel. Ultima varianta, care la prima vedere pare cea mai buna era folosind DataServiceContext.
Aceasta solutie este viabila, atata timp cat nu trebe sa facem un query direct pe tabel. In acest moment tabelel din Windows Azure nu suporta pe query expresii de genu:
  • Contains
  • Count
  • Select
Din aceasta cauza, daca avem o propietate de tip lista nu o sa putem avea un query de genul:
(item => item.ListaElemente.Contains(id)
Din aceasta cauza, pentru a putea face un astfel de query ar fi nevoie sa incarcam toate elementele din tabel si sa le procesam din cod, cea ce nu tocmai optim.
Dar nici prima varianta nu se poate folosii din pacate( lista sa fie stocata ca si un string cu un caracter despartitor), din cauza ca urmatorul query nu este suportat:
(item => item.ListaElementeSz.Contains(id.ToString())
Nu putem sa avem un query care sa foloseasca metoda Contains() pe string.

Singura varianta ramasa este a 2-a, folosirea unei tabele intermediare .

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