为postgreSQL创建扩展

Question

We are creating a simple extension for postgres via Visual Studio, which crashes at building with error: "unresolved external symbol _pg_detoast_datum referenced in function _foo"

#include "postgres.h"
#include<sys/types.h>
#include<sys/stat.h>
#include "fmgr.h"

#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif

/* Add a prototype marked PGDLLEXPORT */
PGDLLEXPORT Datum foo(PG_FUNCTION_ARGS);

PG_FUNCTION_INFO_V1(foo);

Datum 
foo(PG_FUNCTION_ARGS)
{
    text *arg = PG_GETARG_TEXT_P(0); // <-- error appears to be here

    PG_RETURN_INT32(1);
}

If we change text *arg = PG_GETARG_TEXT_P(0) to int32 arg = PG_GETARG_INT32(0) it works fine;

Answer 1

The problem was that VS requires x86 PostgreSQL version (not x64) to build the project.

PS> For the future readers. Pavel Stehule's provided a link to a realy usefull tutorial for building PostgreSQL extensions in VS - http://blog.2ndquadrant.com/compiling-postgresql-extensions-visual-studio-windows/