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I have a problem, that came up recently, when trying to pass boolean parameters to a stored procedure in Firebird 3.

For boolean I use a domain "dom_boolean" that is declared as a char (1) and holds 'T' for true and 'F' for false.
Now I have a stored procedure with boolean parameters. Somthing like this:

create procedure someprocedure (par1 dom_boolean)

returns (result integer) as

begin
.....
suspend;
end^

In Delphi I use it like:

somebooleanvariable := true;
.....
query.sql.text := 'select result from someprocedure (:par1)';
query.parambyname ('par1').asboolean := somebooleanvariable;
query.open;

In Firebird 2.5 that works fine. In Firebird 3.0 I get an exception with something like that "arithmetic exception, numeric overflow, or string truncation string right truncation" and it claims that length should by 4 but is only 1.
So it looks to me, that the type of the boolean parameter should be a 4 byte type and not a 1 byte, like my dom_boolean.

Unfortunately that worked for years with Firebird 2.5 and I have many of that in my projects.
I made a quick and dirty workaround to use parambyname ('par1').asstring and assign 'T' or 'F' depending if it should be true or false, but that is a bit of a mess, because I always have to pay attention to not use asboolean for parameters and

query.parambyname ('par1').asboolean := somebooleanvariable;

is way better than

if somebooleanvariable then
query.parambyname ('par1').asstring := 'T'
else
query.parambyname ('par1').asstring := 'F';

Any suggestions how to deal with that or explanation why this has changed with FB3?

Thank you for the information.
We investigated the problem and found that this error is caused by the specifics of the Firebird 3 functionality, in which the BOOLEAN data type was added. We investigated this feature and inform you about the result.
As a temporary solution, you can use the following string instead of

Thanks for the quick reply.

The problem ist, that I use a char(1) as boolean and that contains 'T' or 'F'.

In the stored procedure I use something like that:

if (:par1 = 'T') then
.......

So when I use
query.parambyname ('par1'). AsInteger: = Integer (somebooleanvariable);

I think it would not deliver 'T' or 'F' but 1 and 0 to the stored procedure.

So have to use asstring and pas 'T' or 'F' to it, depending on somebooleanvariable is true or false.

We have answered you via e-mail.

Yes, thank you. I am working on an example. Will take some time, but I hope I will have it ready in the next few days.

Thank you for the interest to our product.
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