sql - How do I write the join in this query? -

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i have following case :

two tables structure :

[machine] (parent table):

machine_id (pk) | machine_name | desc

[machine_in_out] (child table):

id (pk) | machine_in_id | machine_out_id

now want name of machine_in_id, machine_out_id through parent table.

how make join?!

try this...

select  mio.id,          m1.machine_name,          m2.machine_name    [machine_in_out] mio join    [machine] m1         on  mio.machine_in_id = m1.machineid join    [machine] m2         on  mio.machine_out_id = m2.machineid

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