Jd/Ops join

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ref [option] tab1 col1a ... tab2 col2a ...

creates ref col in tab1 that has data necessary to do joins

col types int1/int2/int4/float/varbyte not allowed

elided option creates simple data for a left1 join

/left option creates more complicated data necessary for a left join

/left ref only works with single joins - f,f-g works and f,f-g,g-h fails

data for left1 or inner join can be derived from the left data

insert/delete/update to either table sets ref col dirty flag

ref col recalculated (dirty) as required

get ref col names with:

jd'info ref' 

drop a ref col by name as you would any other col