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a) First an observation about populating
tables.
The standard syntax for literal values is to put
single quotes around all the strings and not around the numbers eg
insert into table values ('London', 12,
15.7);
However when bulk loading from files it needs an
extra step to find out which fields to put the quotes around. By
experimenting, I have found that the INSERT command will allow quotes around all
the fields eg
insert into table values ('London', '12', '15.7');
but not the converse
insert into table values (London, 12,
15.7);
On the other hand the COPY FROM file command has it
the other way round - if the separators are semi-colons then the source
file
London;12;15.7
Paris;13;22.2
will work
but
'London'; '12'; '15.7'
'Paris';'13';'22.2'
will not!
Any comments? If this behaviour works it is
certainly convenient as well as surprising, provided one knows what to
do!
b) My source files for populating the database
tables have three header lines. It would be convenient if the COPY FROM
command had another parameter eg "HEADERS n" meaning skip first n lines of input
file. Assuming I have not missed something in the manual, would it be
possible to request an enhancement along these lines? The R
statistical package allows one to skip n header lines so this must be a common
situation. My current workaround uses a perl pipe but I would prefer
a cleaner solution.
Regards
Kenneth Evans
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