| From: | Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us> | 
|---|---|
| To: | lockhart(at)alumni(dot)caltech(dot)edu (Thomas G(dot) Lockhart) | 
| Cc: | docs(at)postgresql(dot)org (PostgreSQL-documentation) | 
| Subject: | UNION docs | 
| Date: | 1999-03-19 02:21:03 | 
| Message-ID: | 199903190221.VAA13530@candle.pha.pa.us | 
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| Thread: | |
| Lists: | pgsql-docs | 
I't unnI don't understand this:
    The UNION operator specifies a table derived from a Cartesian product.
    The two tables that represent the direct operands of the UNION must
    have the same number of columns, and corresponding columns must be
    of compatible data types.</para>
    
Why do you call it a cartesian product.  I thought a cartesian product
was tableA x tableB, while UNION is really tableA + tableB, right?
If I am right, can you change the docs? I will leave it as is. Thanks.
-- 
  Bruce Momjian                        |  http://www.op.net/~candle
  maillist(at)candle(dot)pha(dot)pa(dot)us            |  (610) 853-3000
  +  If your life is a hard drive,     |  830 Blythe Avenue
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