Postgresql-C连接测试源代码

/* * MyDBTest.c * *  Created on: 2012-5-2 *      Author: root */#include<stdio.h>#include<stdlib.h>#include<libpq-fe.h>void exit_nicely(PGconn * conn){    PQfinish(conn);    exit(1);}int main(){PGconn *conn;conn = PQconnectdb("host = localhost port = 5432 dbname = root user = root password = 123456");if(PQstatus(conn) != CONNECTION_OK){printf("connect db fail\n");printf("err = %s", PQerrorMessage(conn));//错误信息exit_nicely(conn);}PGresult *res;if((res = PQexec(conn, "SELECT * from file_type_info ;")) == NULL){printf("PQexec error\n");PQclear(res);exit_nicely(conn);}int nfields = PQnfields(res);int i=0;for(; i<nfields; i++){printf("%-50s",PQfname(res, i));}printf("\n");int j=0;for(i=0; i<PQntuples(res); i++){for(; j<nfields; j++){printf("%-50s",PQgetvalue(res,i,j));    //二维数组}printf("\n");}PQclear(res);    //follow each PQexecPQfinish(conn);return 0;}