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More cleanup of CREATE FUNCTION examples.

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This commit is contained in:
Tom Lane
2001-10-26 21:17:03 +00:00
parent 8dcf998dd1
commit 8394e4723a
8 changed files with 45 additions and 39 deletions
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14
doc/src/sgml/ref/create_function.sgml
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@ -1,5 +1,5 @@
<!--
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.27 2001/10/02 21:39:35 tgl Exp $
$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.28 2001/10/26 21:17:03 tgl Exp $
-->
<refentry id="SQL-CREATEFUNCTION">
@ -295,14 +295,16 @@ SELECT one() AS answer;
<para>
The next example creates a C function by calling a routine from a
user-created shared library. This particular routine calculates a
check digit and returns TRUE if the check digit in the function
user-created shared library named <filename>funcs.so</> (the extension
may vary across platforms). The shared library file is sought in the
server's dynamic library search path. This particular routine calculates
a check digit and returns TRUE if the check digit in the function
parameters is correct. It is intended for use in a CHECK
constraint.
<programlisting>
CREATE FUNCTION ean_checkdigit(char, char) RETURNS boolean
AS '/usr1/proj/bray/sql/funcs.so' LANGUAGE C;
AS 'funcs' LANGUAGE C;
CREATE TABLE product (
id char(8) PRIMARY KEY,
@ -318,7 +320,9 @@ CREATE TABLE product (
This example creates a function that does type conversion between the
user-defined type complex, and the internal type point. The
function is implemented by a dynamically loaded object that was
compiled from C source. For <productname>PostgreSQL</productname> to
compiled from C source (we illustrate the now-deprecated alternative
of specifying the exact pathname to the shared object file).
For <productname>PostgreSQL</productname> to
find a type conversion function automatically, the SQL function has
to have the same name as the return type, and so overloading is
unavoidable. The function name is overloaded by using the second