mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-11-27 07:21:09 +08:00
41f862ba87
three functions which exercise the tablefunc API.
show_all_settings()
- returns the same information as SHOW ALL, but as a query result
normal_rand(int numvals, float8 mean, float8 stddev, int seed)
- returns a set of normally distributed float8 values
- This routine implements Algorithm P (Polar method for normal
deviates) from Knuth's _The_Art_of_Computer_Programming_, Volume 2,
3rd ed., pages 122-126. Knuth cites his source as "The polar
method", G. E. P. Box, M. E. Muller, and G. Marsaglia,
_Annals_Math,_Stat._ 29 (1958), 610-611.
crosstabN(text sql)
- returns a set of row_name plus N category value columns
- crosstab2(), crosstab3(), and crosstab4() are defined for you,
but you can create additional crosstab functions per directions
in the README.
Joe Conway
40 lines
1.4 KiB
C
40 lines
1.4 KiB
C
/*
|
|
* tablefunc
|
|
*
|
|
* Sample to demonstrate C functions which return setof scalar
|
|
* and setof composite.
|
|
* Joe Conway <mail@joeconway.com>
|
|
*
|
|
* Copyright 2002 by PostgreSQL Global Development Group
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software and its
|
|
* documentation for any purpose, without fee, and without a written agreement
|
|
* is hereby granted, provided that the above copyright notice and this
|
|
* paragraph and the following two paragraphs appear in all copies.
|
|
*
|
|
* IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
|
|
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
|
|
* LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
|
|
* DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
|
|
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
|
|
* ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
|
|
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
|
|
*
|
|
*/
|
|
|
|
#ifndef TABLEFUNC_H
|
|
#define TABLEFUNC_H
|
|
|
|
/*
|
|
* External declarations
|
|
*/
|
|
extern Datum show_all_settings(PG_FUNCTION_ARGS);
|
|
extern Datum normal_rand(PG_FUNCTION_ARGS);
|
|
extern Datum crosstab(PG_FUNCTION_ARGS);
|
|
|
|
#endif /* TABLEFUNC_H */
|