SQL-sætning til at forbinde og give resultat i flere kolonner

Du har ikke specificeret RDBMS, men dette er grundlæggende en pivot hvis din database har adgang til den funktion. Hvis ikke, kan du replikere ved hjælp af en case og en samlet funktion.

MySQL :

select name,
  sum(case when group_rn = 1 then amount else 0 end) Amount1,
  sum(case when group_rn = 2 then amount else 0 end) Amount2,
  sum(case when group_rn = 3 then amount else 0 end) Amount3
from
(
  select name,
    @num := if(@name = `name`, @num + 1, 1) as group_rn,
    @name := `name` as dummy,
    amount
  from
  (
    select p.name,
      d.amount,
      d.decl_id
    from person p
    inner join declaration d
      on p.person_id = d.person_id
  ) src
  order by name
) p
group by name

Se SQL Fiddle with Demo

I SQL Server og Oracle er PIVOT funktion eksisterer:

SQL-server :

select name,
  [1] as Amount1,
  [2] as Amount2,
  [3] as Amount3
from
(
  select p.name,
    d.amount,
    row_number() over(partition by p.name order by d.amount) rn
  from person p
  inner join declaration d
    on p.person_id = d.person_id
) src
pivot
(
  sum(amount)
  for rn in ([1], [2], [3])
) p

Se SQL Fiddle with Demo

Du kan oprette dynamiske versioner, hvis du har et ukendt antal beløb, som du ønsker at omdanne til kolonner.

Rediger, du har angivet, at du bruger Oracle, så oracle-specifikke svar er nedenfor:

Oracle 11g har pivot funktion:

select name,
  Amount1,
  Amount2,
  Amount3
from
(
  select p.name,
    d.amount,
    row_number() over(partition by p.name order by d.amount) rn
  from person p
  inner join declaration d
    on p.person_id = d.person_id
) src
pivot
(
  sum(amount)
  for rn in ('1' as Amount1, '2' as Amount2, '3' as Amount3)
) p

Se SQL Fiddle with Demo

Hvis du ikke er på Oracle 11g, skal du bruge en CASE med aggregeret funktion:

select name,
  sum(case when rn = 1 then amount else 0 end) Amount1,
  sum(case when rn = 2 then amount else 0 end) Amount2,
  sum(case when rn = 3 then amount else 0 end) Amount3
from
(
  select p.name,
    d.amount,
    row_number() over(partition by p.name order by d.amount) rn
  from person p
  inner join declaration d
    on p.person_id = d.person_id
) src
group by name

Se SQL Fiddle with Demo