select * from a
....+....1...
MYKEY  MYDATA
  A    B 
  B    C 

select * from b
....+....1....+
MYKEY  ITSDATA 
  A    HI 

1. An unspecified join seems to be equal to an inner join - data must 
exist in both files.
SELECT A.MYKEY,A.MYDATA,B.ITSDATA FROM A
JOIN B USING (MYKEY) 
and
SELECT A.MYKEY,A.MYDATA,B.ITSDATA FROM A
inner JOIN B USING (MYKEY) 
both return only
....+....1....+....2..
MYKEY  MYDATA  ITSDATA
  A    B       HI 


2. LEFT JOIN seems to be equal to LEFT OUTER JOIN - pull from first/left 
most file all
records and any matching (if any) from the second file

SELECT A.MYKEY,A.MYDATA,B.ITSDATA FROM A LEFT JOIN B USING (MYKEY)
....+....1....+....2..
MYKEY  MYDATA  ITSDATA
  A    B       HI 
  B    C       - 

SELECT A.MYKEY,A.MYDATA,B.ITSDATA FROM A
LEFT OUTER JOIN B USING (MYKEY) 
....+....1....+....2..
MYKEY  MYDATA  ITSDATA
  A    B       HI 
  B    C       - 


3. Don't know if any of the tools in iNav will allow you to see where the 
person is being dropped.  But I have heard that the set of tools in iNav 
are so darn good for analysis that one shop switched from SQL Server on 
that basis alone.

Rob Berendt




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