Hello
2013/1/4 Kirk Wythers
<kirk.wythers@gmail.com>I am trying to re-cast a column as a timestamp>
ALTER TABLE sixty_min ALTER COLUMN time2 TYPE timestamp;
ERROR: column "time2" cannot be cast to type timestamp without time zone
The column time2 is currently a varchar. I actually do not want to mess with time zones, but it seems that postgres will not let me do this. The actual values in the column time2 look like this:
Is this possible?
yes. it is possible
postgres=# create table foo(a timestamp);
CREATE TABLE
postgres=# insert into foo values(now());
INSERT 0 1
postgres=#
postgres=# alter table foo alter column a type varchar;
ALTER TABLE
postgres=# alter table foo alter column a type timestamp;
ERROR: column "a" cannot be cast automatically to type timestamp without time zone
HINT: Specify a USING expression to perform the conversion.
postgres=# alter table foo alter column a type timestamp using a::timestamp;
ALTER TABLE
postgres=#
Regards
Pavel Stehule