>>>> "Glenn" == Glenn Waldron <gwaldron@wareonearth.com> writes:
Glenn> Using Postgres 6.5 beta (snap 12 apr), on Linux i386. I moved up from Glenn> 6.4.2 when I couldn't get
thingsworking.
Glenn> I'm having difficulty dealing with null text/varchar fields. I need Glenn> to be able to interpret null
valuesas the null string '' for the Glenn> purposes on concatenation.
Glenn> 1) ---- Glenn> For example, the query:
Glenn> SELECT (field_one || field_two) from t1;
Glenn> Will return the concatenation of the two fields. If either of the fields
Glenn> is null, it is interpreted as the empty string '' and the correct answer Glenn> is printed.
Correct ?
I have a table:
david=> \d t
Table = t
+----------------------------------+----------------------------------+-------+| Field |
Type | Length|+----------------------------------+----------------------------------+-------+| a
| text | var || b | text
| var |+----------------------------------+----------------------------------+-------+
david=> insert into t values (NULL, '1111');
INSERT 26656 1
david=> insert into t values ('2222', NULL);
INSERT 26657 1
david=> select a||b from t;
?column?
--------
(2 rows)
But I expect something like:
1111
2222
not 2 empty strings. It is wrong ?
================================================
And yet, I found bug in cast. Try on table above:
select a::int from t;
... this will crash backend on field with NULL value ....
I have postgres 6.5beta1 compiled by egcs-1.1.2 on linux box with
IBM 6x86L processor ...
--
* David Sauer, student of Czech Technical University
* electronic mail: davids@orfinet.cz (mime compatible)
