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Re: alter table add column - specify where the column will go?

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* Grzegorz JaÅkiewicz:

> just never use SELECT *, but always call columns by names. You'll
> avoid having to depend on the order of columns, which is never
> guaranteed, even if the table on disk is one order, the return columns
> could be in some other.

This can't be true because several SQL features rely on deterministic
column order.  Here's an example:

SELECT 1 AS a, 2 AS b UNION SELECT 3 AS b, 4 AS a;

 a | b 
---+---
 1 | 2
 3 | 4
(2 rows)

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