[BUGS] BUG #1888: bug in cast from float4 to float8
The following bug has been logged online: Bug reference: 1888 Logged by: Pablo Oses Email address: [EMAIL PROTECTED] PostgreSQL version: 8.0.x and 7.2.x Operating system: redhat, slackware and win32 Description:bug in cast from float4 to float8 Details: this is *really* simple execute something like this: select cast(123.456::float4 as float8) what do you think its the answer ? 123.456 ? well pgsql 7.2.2, 8.0.0, 8.0.1 and 8.0.3 (all i have used) answers this: 123.456001281738 which is WRONG bye and thanks for a wonderfull contribution for the free software comunity ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
Re: [BUGS] BUG #1886: Bug in SQL parsing
Well spotted! :-) It looks like the bug must actually be with Hibernate, which generated the offending code. I'll take it up with those guys. Thanks for your help! Pete Stephan Szabo wrote: On Fri, 16 Sep 2005, Pete Beck wrote: The following bug has been logged online: Bug reference: 1886 Logged by: Pete Beck Email address: [EMAIL PROTECTED] PostgreSQL version: 8.0.1 & 8.0.3 Operating system: Linux and Windows Description:Bug in SQL parsing Details: Postgres incorrectly reports a relation is being missing in a SQL. The following query reports: ERROR: relation "product0_" does not exist I believe this error is correct. It looks to me like you have: A Left join B on condition, C left join D on condition2 where condition2 refers to A. IIRC, in standard SQL, the scope for condition contains A and B and the scope for condition2 contains C and D but not A. ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
Re: [BUGS] BUG #1888: bug in cast from float4 to float8
"Pablo Oses" <[EMAIL PROTECTED]> writes: > select cast(123.456::float4 as float8) > what do you think its the answer ? 123.456 ? > well pgsql 7.2.2, 8.0.0, 8.0.1 and 8.0.3 (all i have used) answers this: > 123.456001281738 which is WRONG This is not a bug. Please go learn something about floating-point arithmetic (or if you don't care to, use type numeric instead). regards, tom lane ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
Re: [BUGS] BUG #1888: bug in cast from float4 to float8
On Sat, Sep 17, 2005 at 04:00:50AM +0100, Pablo Oses wrote: > select cast(123.456::float4 as float8) > > what do you think its the answer ? 123.456 ? > > well pgsql 7.2.2, 8.0.0, 8.0.1 and 8.0.3 (all i have used) answers this: > 123.456001281738 which is WRONG Float4 has a precision of only about 6 digits, so you can't assume much about the digits beyond that. See the documentation for floating-point types: http://www.postgresql.org/docs/8.0/interactive/datatype.html#DATATYPE-FLOAT This is hardly a behavior unique to PostgreSQL; use a search engine to find explanations of the problems of using binary floating-point numbers. If you need exact results then use the numeric type. -- Michael Fuhr ---(end of broadcast)--- TIP 6: explain analyze is your friend
[BUGS] BUG #1889: little documentation error
The following bug has been logged online: Bug reference: 1889 Logged by: Evgeny Gridasov Email address: [EMAIL PROTECTED] PostgreSQL version: 8.1 Operating system: n/a Description:little documentation error Details: http://developer.postgresql.org/docs/postgres/manage-ag-tablespaces.html see the text: -- To define a tablespace, use the CREATE DATABASE command, for example: CREATE TABLESPACE fastspace LOCATION '/mnt/sda1/postgresql/data'; -- i guess the text should be "use the CREATE TABLESPACE" command =) ---(end of broadcast)--- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq
Re: [BUGS] BUG #1889: little documentation error
"Evgeny Gridasov" <[EMAIL PROTECTED]> writes: > see the text: > To define a tablespace, use the CREATE DATABASE command, for example: > CREATE TABLESPACE fastspace LOCATION '/mnt/sda1/postgresql/data'; > i guess the text should be "use the CREATE TABLESPACE" command =) Yup --- thanks for catching it! regards, tom lane ---(end of broadcast)--- TIP 6: explain analyze is your friend
