Another one! :) How to convert char(1) to boolean without re-exporting tables.
Ok. This time it's a bit more difficult ;)
I'd like to convert my char(1) stuff to boolean without having to kill
the table and re-export the original from MSAccess. I think there's a
way to do that since just creating a new table with bool instead of
char(1) won't let me insert into it the values contained in the old
table seeing they're not of the same type.
Thanks as always!! :)
Valerio Santinelli
tanis@mediacom.it
At 16:58 +0200 on 19/1/99, Valerio Santinelli wrote:
char(1) won't let me insert into it the values contained in the old
table seeing they're not of the same type.
Why not? It all depends on how you populate the new table. You do that
usually with a SELECT statement. A select statement like
SELECT field_1, field_2, ( char_field = '1' ), field 4, field5...
gives you a boolean expression - is the char_field equal to '1' at the
current row?
Some versions of Postgres crash when given a boolean expression on the
select target list. In that case you can define it as a function
CREATE FUNCTION is_one( bpchar ) RETURNS bool
AS 'SELECT $1 = ''1'''
LANGUAGUE 'sql';
And then do the select as
SELECT field_1, field_2, is_one( char_field), field4, field5....
Herouth
--
Herouth Maoz, Internet developer.
Open University of Israel - Telem project
http://telem.openu.ac.il/~herutma