Fixup for src/tutorial/func.c and src/tutorial/func.source

Removed char16 and replaced with an example using Point
as suggested by Tom Lane.  The dept field was changed to
the cubicle field denoting the row(x) and column(y) of
the employee's cube in the corporate jungle.  The C function
builds a 'compromise' cubicle from two suggested ones.

I'll try and patchup the documentation next.

Clark

diff --git a/src/tutorial/funcs.c b/src/tutorial/funcs.c
index 77eec35b7295ff62b8d8bc4b50210fa963af19ca..cda3ef112a957b58698187b96945b578bc892dfb 100644 (file)
--- a/src/tutorial/funcs.c
+++ b/src/tutorial/funcs.c
@@ -8,21 +8,21 @@
 
 #include <string.h>
 #include <stdio.h>
-#include "postgres.h"                  /* for char16, etc. */
+#include "postgres.h"                  /* for variable length type */
 #include "utils/palloc.h"              /* for palloc */
-#include "libpq-fe.h"                  /* for TUPLE */
 #include "executor/executor.h" /* for GetAttributeByName() */
+#include "utils/geo_decls.h"   /* for point type */
 
 /* The following prototypes declare what we assume the user declares to
    Postgres in his CREATE FUNCTION statement.
 */
 
 int                    add_one(int arg);
-char16    *concat16(char16 * arg1, char16 * arg2);
+Point     *makepoint(Point *pointx, Point *pointy );
 text      *copytext(text *t);
 
-bool c_overpaid(TUPLE t,                               /* the current instance of EMP */
-                  int4 limit);
+bool c_overpaid(TupleTableSlot *t,       /* the current instance of EMP */
+                               int4 limit);
 
 
 
@@ -32,14 +32,15 @@ add_one(int arg)
        return arg + 1;
 }
 
-char16 *
-concat16(char16 * arg1, char16 * arg2)
+Point *
+makepoint(Point *pointx, Point *pointy )
 {
-       char16     *new_c16 = (char16 *) palloc(sizeof(char16));
+       Point     *new_point = (Point *) palloc(sizeof(Point));
 
-       MemSet(new_c16, 0, sizeof(char16));
-       strncpy((char *) new_c16, (char *) arg1, 16);
-       return (char16 *) (strncat((char *) new_c16, (char *) arg2, 16));
+       new_point->x = pointx->x;
+       new_point->y = pointy->y;
+
+       return new_point;
 }
 
 text *
@@ -66,7 +67,7 @@ copytext(text *t)
 }
 
 bool
-c_overpaid(TUPLE t,                            /* the current instance of EMP */
+c_overpaid(TupleTableSlot *t,   /* the current instance of EMP */
                   int4 limit)
 {
        bool            isnull = false;

diff --git a/src/tutorial/funcs.source b/src/tutorial/funcs.source
index f2306839246639e8c222eb16bd880a1f5f24c1ee..b8e03218fd96b77a9d500b19358e4bdf8da8fb23 100644 (file)
--- a/src/tutorial/funcs.source
+++ b/src/tutorial/funcs.source
@@ -1,12 +1,12 @@
 ---------------------------------------------------------------------------
 --
 -- funcs.sql-
---    Tutorial on using functions in POSTGRES.
+--       Tutorial on using functions in POSTGRES.
 --
 --
 -- Copyright (c) 1994-5, Regents of the University of California
 --
--- $Id: funcs.source,v 1.2 1998/02/11 03:51:38 thomas Exp $
+-- $Id: funcs.source,v 1.3 1999/03/14 15:22:15 momjian Exp $
 --
 ---------------------------------------------------------------------------
 
@@ -52,14 +52,14 @@ CREATE TABLE EMP (
        name            text,
        salary          int4,
        age             int4,
-       dept            char16
+       cubicle         point
 );
 
-INSERT INTO EMP VALUES ('Sam', 1200, 16, 'toy');
-INSERT INTO EMP VALUES ('Claire', 5000, 32, 'shoe');
-INSERT INTO EMP VALUES ('Andy', -1000, 2, 'candy');
-INSERT INTO EMP VALUES ('Bill', 4200, 36, 'shoe');
-INSERT INTO EMP VALUES ('Ginger', 4800, 30, 'candy');
+INSERT INTO EMP VALUES ('Sam', 1200, 16, '(1,1)');
+INSERT INTO EMP VALUES ('Claire', 5000, 32, '(1,2)');
+INSERT INTO EMP VALUES ('Andy', -1000, 2, '(1,3)');
+INSERT INTO EMP VALUES ('Bill', 4200, 36, '(2,1)');
+INSERT INTO EMP VALUES ('Ginger', 4800, 30, '(2,4)');
 
 -- the argument of a function can also be a tuple. For instance, 
 -- double_salary takes a tuple of the EMP table
@@ -69,7 +69,7 @@ CREATE FUNCTION double_salary(EMP) RETURNS int4
 
 SELECT name, double_salary(EMP) AS dream
 FROM EMP
-WHERE EMP.dept = 'toy';
+WHERE EMP.cubicle ~= '(2,1)'::point;
 
 -- the return value of a function can also be a tuple. However, make sure 
 -- that the expressions in the target list is in the same order as the 
@@ -77,9 +77,9 @@ WHERE EMP.dept = 'toy';
 
 CREATE FUNCTION new_emp() RETURNS EMP
    AS 'SELECT \'None\'::text AS name,
-              1000 AS salary,
-              25 AS age,
-              \'none\'::char16 AS dept'
+                         1000 AS salary,
+                         25 AS age,
+                         \'(2,2)\'::point AS cubicle'
    LANGUAGE 'sql';
 
 -- you can then project a column out of resulting the tuple by using the
@@ -99,33 +99,36 @@ SELECT name(high_pay()) AS overpaid;
 -----------------------------
 -- Creating SQL Functions with multiple SQL statements
 --     you can also create functions that do more than just a SELECT.
+--
+-- 14MAR99 Clark Evans: Does not quite work, commented out for now.
+--
 -----------------------------
 
 -- you may have noticed that Andy has a negative salary. We'll create a
 -- function that removes employees with negative salaries.
-
-SELECT * FROM EMP;
-
-CREATE FUNCTION clean_EMP () RETURNS int4
-   AS 'DELETE FROM EMP WHERE EMP.salary <= 0\;
-       SELECT 1 AS ignore_this'
-   LANGUAGE 'sql';
-
-SELECT clean_EMP();
-
-SELECT * FROM EMP;
+--
+-- SELECT * FROM EMP;
+--
+-- CREATE FUNCTION clean_EMP () RETURNS int4
+--       AS 'DELETE FROM EMP WHERE EMP.salary <= 0\;
+--               SELECT 1 AS ignore_this'
+--       LANGUAGE 'sql';
+--
+-- SELECT clean_EMP();
+--
+-- SELECT * FROM EMP;
 
 
 -----------------------------
 -- Creating C Functions
 --     in addition to SQL functions, you can also create C functions. 
---     See C-code/funcs.c for the definition of the C functions.
+--     See funcs.c for the definition of the C functions.
 -----------------------------
 
 CREATE FUNCTION add_one(int4) RETURNS int4
    AS '_OBJWD_/funcs.so' LANGUAGE 'c';
 
-CREATE FUNCTION concat16(char16, char16) RETURNS char16
+CREATE FUNCTION makepoint(point, point) RETURNS point
    AS '_OBJWD_/funcs.so' LANGUAGE 'c';
 
 CREATE FUNCTION copytext(text) RETURNS text
@@ -136,7 +139,7 @@ CREATE FUNCTION c_overpaid(EMP, int4) RETURNS bool
 
 SELECT add_one(3) AS four;
 
-SELECT concat16('abc', 'xyz') AS newchar16;
+SELECT makepoint('(1,2)'::point, '(3,4)'::point ) AS newpoint;
 
 SELECT copytext('hello world!');
 
@@ -148,9 +151,10 @@ WHERE name = 'Bill' or name = 'Sam';
 
 DROP FUNCTION c_overpaid(EMP, int4);
 DROP FUNCTION copytext(text);
-DROP FUNCTION concat16(char16,char16);
+DROP FUNCTION makepoint(point,point);
 DROP FUNCTION add_one(int4);
 DROP FUNCTION clean_EMP();
+DROP FUNCTION high_pay();
 DROP FUNCTION new_emp();
 DROP FUNCTION add_em(int4, int4);
 DROP FUNCTION one();