Thread: Re: [GENERAL] id and ID in CREATE TABLE
Thanks all for comments. In Oracle and DB2 as far as I know the upper case column names are used when you have no columns quoted.. Indeed it is recommended to use lower cases to avoid mistakes and confusion during porting. Is that right ? But anyway this is not so important, but why upper cases are bad ? Why then Oracle , IBM is using them and why the SQL standard is not changed ? stefan On Fri, 19 Jul 2002, Martijn van Oosterhout wrote: > On Sat, Jul 20, 2002 at 10:39:52AM +0300, stefan@extum.com wrote: > > > > I forgot about "" Sorry. So if I would use names quoted then my questions > > are obsolete. Except one: > > > > So actually the only strange part would be PostgreSQL is folding to lower > > cases a column name ... > > [snip] > > > Why is like this ? Why not letting them upper case if they are not quoted > > ? > > I think it's because many people think that uppercase column names suck. And > I agree with them. If you follow the given advice (either always quote > column names or never) then not only will your program work, it's will be > completely portable. > > So, if you'd used your CREATE TABLE statememnt below, you wouldn't have had > this problem. > > > > CREATE TABLE ttt ( > > > > > > ID int2, > > > name text ); >
stefan@extum.com writes:
> But anyway this is not so important, but why upper cases are bad ?
It's well established that all-lower-case text is more readable than
all-upper-case ... at least in English; but I think the same would be
true of any language using an approximately Roman alphabet. The problem
with upper case is there's less variation in the overall letter shape.
If you don't care to dig in the academic literature about it, here's a
simple experiment: which of the following paragraphs do you find more
readable?
it's well established that all-lower-case text is more readable
than all-upper-case ... at least in english; but i think the
same would be true of any language using an approximately roman
alphabet. the problem with upper case is there's less variation
in the overall letter shape. if you don't care to dig in the
academic literature about it, here's a simple experiment: which
of the following paragraphs do you find more readable?
IT'S WELL ESTABLISHED THAT ALL-LOWER-CASE TEXT IS MORE READABLE
THAN ALL-UPPER-CASE ... AT LEAST IN ENGLISH; BUT I THINK THE
SAME WOULD BE TRUE OF ANY LANGUAGE USING AN APPROXIMATELY ROMAN
ALPHABET. THE PROBLEM WITH UPPER CASE IS THERE'S LESS VARIATION
IN THE OVERALL LETTER SHAPE. IF YOU DON'T CARE TO DIG IN THE
ACADEMIC LITERATURE ABOUT IT, HERE'S A SIMPLE EXPERIMENT: WHICH
OF THE FOLLOWING PARAGRAPHS DO YOU FIND MORE READABLE?
For me, at least, the second version takes noticeably more time to read
and is certainly less pleasant. (I suppose that for a non-native
speaker of English, mental translation might slow you down to the point
where you don't notice a difference. If so, try it on a random
paragraph in your own language.)
For PostgreSQL there is also a backwards compatibility issue: if we
change this decision now, we'd cause all kinds of problems for existing
code and databases.
> Why then Oracle , IBM is using them and why the SQL standard is not
> changed ?
The SQL standard's choice in this matter is prehistoric; undoubtedly
it falls out of the days when computer printers only had one type case.
IBM probably still has a residual fondness for those days ;-). But
the rest of the industry figured out that lower case was better
somewhere around 1960, cf Algol-60 which was the first language to spell
its keywords preferentially in lower case.
regards, tom lane
Tom Lane wrote:<br /><blockquote cite="mid12220.1027085465@sss.pgh.pa.us" type="cite"><pre wrap=""><a
class="moz-txt-link-abbreviated"href="mailto:stefan@extum.com">stefan@extum.com</a> writes: </pre><blockquote
type="cite"><prewrap="">But anyway this is not so important, but why upper cases are bad ? </pre></blockquote><pre
wrap="">
It's well established that all-lower-case text is more readable than
all-upper-case ... at least in English; but I think the same would be
true of any language using an approximately Roman alphabet. The problem
with upper case is there's less variation in the overall letter shape.
If you don't care to dig in the academic literature about it, here's a
simple experiment: which of the following paragraphs do you find more
readable?
it's well established that all-lower-case text is more readablethan all-upper-case ... at least in english; but i think
thesamewould be true of any language using an approximately romanalphabet. the problem with upper case is there's less
variationinthe overall letter shape. if you don't care to dig in theacademic literature about it, here's a simple
experiment:whichof the following paragraphs do you find more readable?
IT'S WELL ESTABLISHED THAT ALL-LOWER-CASE TEXT IS MORE READABLETHAN ALL-UPPER-CASE ... AT LEAST IN ENGLISH; BUT I THINK
THESAMEWOULD BE TRUE OF ANY LANGUAGE USING AN APPROXIMATELY ROMANALPHABET. THE PROBLEM WITH UPPER CASE IS THERE'S LESS
VARIATIONINTHE OVERALL LETTER SHAPE. IF YOU DON'T CARE TO DIG IN THEACADEMIC LITERATURE ABOUT IT, HERE'S A SIMPLE
EXPERIMENT:WHICHOF THE FOLLOWING PARAGRAPHS DO YOU FIND MORE READABLE?
For me, at least, the second version takes noticeably more time to read
and is certainly less pleasant. (I suppose that for a non-native
speaker of English, mental translation might slow you down to the point
where you don't notice a difference. If so, try it on a random
paragraph in your own language.)</pre></blockquote> It's a pattern recognition issue. Taken in context with your
readingexperience and the general constructs of the English language in addition common usage, you encounter far more
lowercase letters than upper case letters. It makes sense that it would be easier to recognize the words in all lower
case. Secondly, your brain expects lower case letters behind the leading upper case letter for the word. So in a
senseyou backtrack just a little because it doesn't match what you expect. I'm not discounting the statements you
made,but this is one additional observation.<br /><br /> [ In the previous paragraph there were 6 capital letters to
the471 non-capital letters. ]<br /><blockquote cite="mid12220.1027085465@sss.pgh.pa.us" type="cite"><pre wrap="">
For PostgreSQL there is also a backwards compatibility issue: if we
change this decision now, we'd cause all kinds of problems for existing
code and databases.
</pre><blockquote type="cite"><pre wrap="">Why then Oracle , IBM is using them and why the SQL standard is not
changed ? </pre></blockquote><pre wrap="">
The SQL standard's choice in this matter is prehistoric; undoubtedly
it falls out of the days when computer printers only had one type case.
IBM probably still has a residual fondness for those days ;-). But
the rest of the industry figured out that lower case was better
somewhere around 1960, cf Algol-60 which was the first language to spell
its keywords preferentially in lower case.
regards, tom lane
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On Fri, 19 Jul 2002, Tom Lane wrote: > stefan@extum.com writes: > > But anyway this is not so important, but why upper cases are bad ? > > It's well established that all-lower-case text is more readable than > all-upper-case ... Agreed. Absolutely. But, since the SQL standard says upper case, wouldn't it be useful to at least have a switch (run time, initdb time, or ./configure time???) called something like FOLDTOUPPER (in upper case of course :-) If it's an easy win I'd be willing to do it. I'm not the world's greatest C hacker, but I still remember enough of it to be competant.