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Atomic vs Two Phase
Atomic vs Two Phase
Posted Apr 1, 2004 0:54 UTC (Thu) by ccyoung (subscriber, #16340)Parent article: The Aberdeen Group looks at free databases
Apparently pg has atomic transactions, but not two phase. What is the difference? How important is it?
I wish they had aesthetic issues. IMHO things like different data types for text < 256 chars, < 1024 chars, etc, is plain butt ugly, as well as, for example, having to declare something a "blob" instead of "varchar" is you want case-sensitive comparison.
pg's pgpgsql is quite functional but a bit klutzy, but pg's internal procedures also suport pltcl, pltclu, plperl, plperlu, and plpython, so it's hard to fault that aspect.
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Atomic vs Two Phase
Posted Apr 1, 2004 2:23 UTC (Thu) by stephenjudd (subscriber, #3227) [Link]
Here's an explanation of two phase commit.It's pretty important if your transaction depends on a service outside your DBMS. Eg, think of an order process where the order only gets committed if there's authorisation from a third party. Anywhere with mixed legacy systems in the back end, such as your typical bank, probably would like two phase commit in the DB. It's distributed systems 101.
Like anything else, you can implement this in your application code instead, but it's nice when the DB does it for you, because it's harder to do right than you think.
Atomic vs Two Phase
Posted Apr 5, 2004 15:34 UTC (Mon) by rwmj (subscriber, #5474) [Link]
I wish they had aesthetic issues. IMHO things like different data types for text < 256 chars, < 1024 chars, etc, is plain butt ugly, [...]Well, this is of course an area where PostgreSQL really wins. In PG I always use 'text' for strings of any length. I was horrified recently when doing an Oracle contract to find out that there's still no obvious way to have a string longer than 4000 chars!
Rich.