Extending SQL with a C function

Started by Christoph Lorenzalmost 28 years ago3 messagesgeneral
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#1Christoph Lorenz
ChLorenz@csi.com

Hi,

how can I write a SQL extention in C, which works with "unusual" data
types?

I've managed to write a c function, which accepts int4 as input parameter
and has got int4 as output parameter.

My problem now is, that I want to use a char(10) as input parameter, since
the input for that function is a colum, which is a char(10) type.
How do I do this?

(In the manuals, it is said, one should create an own data type in C - I've
already done this, called it "char10", but of course, I cannot use this
data type in SQL...)

Thank you very much
Christoph
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#2Christoph Lorenz
ChLorenz@csi.com
In reply to: Christoph Lorenz (#1)
Again: [GENERAL] Extending SQL with a C function

Hi,

I still haven't found it out, so here's my question again:

how can I write a SQL extention in C, which works with "unusual" data
types?

I've managed to write a c function, which accepts int4 as input parameter
and has got int4 as output parameter.

My problem now is, that I want to use a char(10) as input parameter, since
the input for that function is a colum, which is a char(10) type.
How do I do this?

(In the manuals, it is said, one should create an own data type in C - I've
already done this, called it "char10", but of course, I cannot use this
data type in SQL...)

Thank you very much
Christoph
--
** http://ourworld.compuserve.com/homepages/ChLorenz/ ** ChLorenz@csi.com **
** No Spam ! ** No Adverts ! ** No Junk-Mails ! ** No unwanted Mails ! **

#3Herouth Maoz
herouth@oumail.openu.ac.il
In reply to: Christoph Lorenz (#2)
Re: Again: [GENERAL] Extending SQL with a C function

At 11:26 +0300 on 2/6/98, Christoph Lorenz wrote:

how can I write a SQL extention in C, which works with "unusual" data
types?

I've managed to write a c function, which accepts int4 as input parameter
and has got int4 as output parameter.

My problem now is, that I want to use a char(10) as input parameter, since
the input for that function is a colum, which is a char(10) type.
How do I do this?

(In the manuals, it is said, one should create an own data type in C - I've
already done this, called it "char10", but of course, I cannot use this
data type in SQL...)

char(10) is not, in fact, an "unusual" datatype. It's what postgres calls
"bpchar" (blank-padded char). I think there is an interface for dealing
with bpchar fields, which carry their own maximum length which you have to
decode before using.

Herouth

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Herouth Maoz, Internet developer.
Open University of Israel - Telem project
http://telem.openu.ac.il/~herutma