Re: [HACKERS] Odd behavior of type coercion for datetime - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: [HACKERS] Odd behavior of type coercion for datetime
Date
Msg-id 199903151437.JAA12447@candle.pha.pa.us
Whole thread Raw
In response to Odd behavior of type coercion for datetime  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [HACKERS] Odd behavior of type coercion for datetime
List pgsql-hackers
Have we dealt with this?


> With 6.4 or current sources, I find that coercing a datetime to float8
> is a no-op:
> 
> treetest=> create table dt1 (t datetime);
> CREATE
> treetest=> insert into dt1 values('now');
> INSERT 159593 1
> treetest=> select t from dt1;
> t
> ----------------------------
> Sun Jan 24 18:28:50 1999 EST
> (1 row)
> 
> treetest=> select t::float8 from dt1;
> ?column?
> ----------------------------
> Sun Jan 24 18:28:50 1999 EST
> (1 row)
> 
> 
> I was expecting to get either some numerical equivalent to the date
> (seconds since 1970 would do nicely, but I'll take the internal rep...)
> or an error message saying "no such conversion available".  I was
> certainly not expecting to find that the result was still a datetime,
> but such it appears to be.  This is a bug, wouldn't you say?
> 
> What's even more curious is that coercing to int4 does produce
> something numeric:
> 
> treetest=> select t::int4 from dt1;
>      int4
> ---------
> -29464270
> (1 row)
> 
> 
>             regards, tom lane
> 
> 


--  Bruce Momjian                        |  http://www.op.net/~candle maillist@candle.pha.pa.us            |  (610)
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