Re: Which column is taken in JOIN with multiple columns and different content ?

In message <45e84bdf$0$23135$9b4e6d93@xxxxxxxxxxxxxxxxxxxxxxxxxxx>, Tobias Merler <merlin@xxxxxxx> writes
Assume I join two tables.
Both of these tables contain a column with name "col1". This column ist not he primary key.
However this column contains different values which value is taken ?

Lets see the following example:

Select *
FROM tablea a, tableb b
Where a.id = b.id

tablea:

id col1 col2

1 aaa ddd
2 bbb eee
3 ccc fff


tableb:

id col1 col3

1 zzz uuu
2 xxx vvv
3 yyy www

The result table will look like:

id col1 col2 col3

1 ??? ddd uuu
2 ??? eee vvv
3 ??? fff www

No.

The result table will look like

id col1 col2 id col1 col3
1 aaa ddd 1 zzz uuu
2 bbb eee 2 xxx vvv
3 ccc fff 3 yyy www

.

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