Search Postgresql Archives

Re: convert integer to bool implicitly

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



I got it working.
This has been bothering me for a long time, but now that it was listed as an official bug in my system, I had to deal with it.

I'll post the solution under a new post, because I think this will help a lot of people.

Sim Zacks wrote:
I know I can do it explicitly, I need to do it implicitly.
I am having a problem with a Microsoft Access front-end , that uses -1 as true and 0 as false. I have everything worked around all the places where I could find it by using a cbool(), but this doesn't work with filters, which probably call a "select where field =-1 or =0." automatically by access.

I get an ODBC error saying that "Operator does not exist: boolean=integer.

I would like to create the implicit conversion, so that it works both without the cbool from now on, and that filters should work fine. I have tried a number of different ODBC settings, and no matter what setting there is always one problem or another that has to be overcome. I can get it all to work if I put a Before Insert and Update trigger and change the -1 to true, but I would have to do that for every boolean field in my application. It would be a lot easier and make sense system-wise to implicitly convert the integer to bool.

Andreas Kretschmer wrote:
Sim Zacks <sim@xxxxxxxxxxxxxx> schrieb:

How easy would it be to write a small type extension to have integer automatically convert to bool? For example, I want an implicit conversion that 0 is false and everything else is true.

test=# \d foo;
      Table "public.foo"
 Column |  Type   | Modifiers
--------+---------+-----------
 val    | integer |

test=# select * from foo;
 val
-----
   0
   1
   2
   3
(4 rows)

test=# select val::bool from foo;
 val
-----
 f
 t
 t
 t
(4 rows)


Is this C programming or can you do it with a local procedural language?

You can use regular casts.


HTH, Andreas


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Postgresql Jobs]     [Postgresql Admin]     [Postgresql Performance]     [Linux Clusters]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Postgresql & PHP]     [Yosemite]
  Powered by Linux