join - SQL table joining different people -

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i join 2 tables showing different information population in table zp there people not shown in wg. add these people zp final table, in columns there no information, have zeros.

select *  mobility.mzmv2010.wegeinland wg join mobility.mzmv2010.zielpersonen zp using ("hhnr","zielpnr")

an example can seen in picture:

image

presumably, want left join . . . person table first:

select coalesce(sum(zp."wp" * "w_rdist")/(62868 * avg(zp."wp")), 0) mobility.mzmv2010.zielpersonen zp left join      mobility.mzmv2010.wegeinland wg      using ("hhnr", "zielpnr") ;

note: should qualify w_rdist column specify table coming from.


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