#include <stdio.h>
#include <stdlib.h>
#include <libpq-fe.h>

int psql_insert(void);
int psql_show(void);
const char *conninfo;
PGconn *conn;
PGresult *res;
int main()
{
conninfo="dbname = postgres user = gpadmin password = ";
conn = PQconnectdb(conninfo);
if (PQstatus(conn) != CONNECTION_OK)
{
fprintf(stderr, “Connection to database failed: %s”,
PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
}

    psql_show();    //查询并打印表中内容
    PQfinish(conn);
    PQclear(res);
    return 0;

}

/查询显示函数/
int psql_show(void)
{
int i = 0,t = 0,s,k;
res = PQexec(conn,“select * from gp_segment_configuration”);
if( PQresultStatus(res) != PGRES_TUPLES_OK)
{
fprintf(stderr,“Exec Query Failed4!\n”);
PQclear(res);
return 0;
}
i = PQntuples(res);//取得查询结果记录数量
t = PQnfields(res);//取得字段数量
for(s=0; s<i;s++)
{
for (k = 0; k<t; k++)
{
printf("%s",PQgetvalue(res,s,k));
printf(" “);
}
printf(”\n");
}
}
gcc -I/usr/local/hawq/include -L/usr/local/hawq/lib -lpq TpsTestTools.c -o TpsTestTools