sql server - SQL: Proper JOIN Protocol -

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i have following tables following attributes:

op(opno, opname, date) opconvert(opno, m_opno, source_id, date) source(source_id, source_name, date) fleet(opno, s_no, date)

i have current multiple join query gives me results want:

select o.opno op_no, o.opname, o.date date_entered, c.*  op o left outer join opconvert c on o.opno = c.opno  left outer join source d on c.source_id = d.source_id c.opno not null

the problem this. need join fleet table on previous multiple join statement attach relevant s_no multiple join table. still able accomplish using left outer join or have use different join statement? also, table join on?

please note familiar left outer joins.

thanks.

i guess in case use inner join or left join (which same thing left outer join in sql server.

  • inner join means return records other tables if there corresponding records (based on join condition) in fleet table.
  • left join means return records other tables if there no corresponding records (based on join condition) in fleet table. columns fleet return null in case.

as table join, should join table makes more logical sense based on data structure.


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