Re: A modest proposal for a FAQ addition

Ian Barwick wrote:
> On Sunday 12 January 2003 06:17, Bruce Momjian wrote:
> > Tom Lane wrote:
> > > Q: Why do I get strange results with a CHAR(n) field?
> > >
> > > A. Don't use CHAR(n). VARCHAR(n) has the behavior you are probably
> > > expecting; on top of which it's more compact and usually faster.
> > >
> > >
> > > I suppose the above needs some fleshing out, but man am I getting tired
> > > of explaining about significant vs non-significant trailing blanks.
> >
> > OK, good point. I was mentioning CHAR() in the FAQ entry first, while
> > it should have been mentioned later. I also added a specific mention of
> > the trailing spaces issue. Patch attached.
>
> Err, from the patch:
>
> "CHAR(n) stores trailing spaces, while VARCHAR(n) trims them."
>
> Surely this should read something like:
>
> "CHAR(n) automatically pads strings with trailing blanks to the defined
> column length."

OK, new text is:

<SMALL>VARCHAR(n)</SMALL> is best when storing variable-length
strings but it limits how long a string can be. <SMALL>TEXT</SMALL>
is for strings of unlimited length, maximum 1 gigabyte.
<P><SMALL>CHAR(n)</SMALL> is for storing strings that are all the
same length. <SMALL>CHAR(n)</SMALL> pads with blanks to the specified
length, while <SMALL>VARCHAR(n)</SMALL> only stores the characters
supplied. <SMALL>BYTEA</SMALL> is for storing binary data,
particularly values that include <SMALL>NULL</SMALL> bytes. These
types have similar performance characteristics.</P>

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