The lvarptr.ec program

The lvarptr.ec example program, which follows, uses lvarchar pointers

/*
**
** Sample use of LVARCHAR to fetch collections in ESQL/C.
**
** Statically determined collection types.
*/

#include <stdio.h>

static void print_lvarchar_ptr(
const char *tag,
EXEC SQL BEGIN DECLARE SECTION;
parameter lvarchar **lv
EXEC SQL END DECLARE SECTION;
)
{
    char *data;

    data = ifx_var_getdata(lv);
    if (data == 0)
        data = "<<NO DATA>>";
    printf("%s: %s\n", tag, data);
}

static void process_stmt(char *stmt)
{
    EXEC SQL BEGIN DECLARE SECTION;
    lvarchar *lv1;
    lvarchar *lv2;
    lvarchar *lv3;
    mint seq;
    char *stmt1 = stmt;
    EXEC SQL END DECLARE SECTION;

    printf("SQL: %s\n", stmt);

    EXEC SQL WHENEVER ERROR STOP;
    EXEC SQL PREPARE p_collect FROM :stmt1;
    EXEC SQL DECLARE c_collect CURSOR FOR p_collect;
    EXEC SQL OPEN c_collect;

    ifx_var_flag(&lv1, 1);
    ifx_var_flag(&lv2, 1);
    ifx_var_flag(&lv3, 1);

    while (sqlca.sqlcode == 0)
    {
        EXEC SQL FETCH c_collect INTO :seq, :lv1, :lv2, :lv3;
        if (sqlca.sqlcode == 0)
        {
            printf("Sequence: %d\n", seq);
            print_lvarchar_ptr("LVARCHAR 1", &lv1);
            print_lvarchar_ptr("LVARCHAR 2", &lv2);
            print_lvarchar_ptr("LVARCHAR 3", &lv3);
            ifx_var_dealloc(&lv1);
            ifx_var_dealloc(&lv2);
            ifx_var_dealloc(&lv3);
        }
    }    

    EXEC SQL CLOSE c_collect;
    EXEC SQL FREE c_collect;
    EXEC SQL FREE p_collect;
}

mint main(int argc, char **argv)
{
    EXEC SQL BEGIN DECLARE SECTION;
    char *dbase = "stores7";
    char *stmt1 =
        "INSERT INTO t_collections VALUES(0, "
        "'LIST{-1,0,-2,3,0,0,32767,249}', 'SET{-1,0,-2,3}', "
        "'MULTISET{-1,0,0,-2,3,0}') ";
    char *data;
    EXEC SQL END DECLARE SECTION;

if (argc > 1)
        dbase = argv[1];
    EXEC SQL WHENEVER ERROR STOP;
    printf("Connect to %s\n", dbase);
    EXEC SQL CONNECT TO :dbase;
 
    EXEC SQL CREATE TEMP TABLE t_collections
    (
        seq serial not null,
        l1 list    (integer  not null),
        s1 set     (integer  not null),
        m1 multiset(integer  not null)
    );
 
    EXEC SQL EXECUTE IMMEDIATE :stmt1;
    EXEC SQL EXECUTE IMMEDIATE :stmt1;
    EXEC SQL EXECUTE IMMEDIATE :stmt1;
 
    process_stmt("SELECT seq, l1, s1, m1 FROM t_collections");
 
    puts("OK");
    return 0;
}