KoldCoffee (10/19/2014)

---

...I incremented the JOIN condition in Eirikur's LEFT JOIN example and found that the entire left table is returned, whether the JOIN condition is <1, <2, <3, <4

SELECT

MT.MT_ID

,MT.MT_DATE

,MT.REF_ID

,RF.REF_VAL

FROM MAIN_TABLE MT

LEFT OUTER JOIN REF RF

ON MT.REF_ID = RF.REF_ID

AND RF.REF_ID < 4;

The AND is joining to only those rows in the right table that satisfy the JOIN criteria.

I think I understand finally.