c connection to MySQL instance

MySQL today to the new colleagues to do MySQL training, the use of an example:
Connect database test username root password ABC
In the inside there is a username table, describe username results are as follows
Mysql> describe username;
+----------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+-------+
| ID | Int (10) | YES | | NULL | |
| Username | varchar (32) | | PRI | | |
+----------+-------------+------+-----+---------+-------+

Mysql> SELECT * from username;
+------+----------+
| ID | Username |
+------+----------+
| 1 | SFS |
+------+----------+
1 row in Set (0.00 sec)


The purpose of this article is to find the Execute SELECT ID from username statement and print the results
Code:
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
MySQL MySQL;
Main ()
{
Char host[32]= "localhost";
Char user[32]= "root";
Char passwd[32]= "ABC";
Char dbname[32]= "Test";

if (Mysql_init (&mysql) = NULL)
{
Syslog (log_user| Log_info, "inital MySQL handle Errorn");
return 1;
}
if (Mysql_real_connect (&mysql,host,user,passwd,dbname,0,null,0) = NULL)
{
Syslog (log_user| Log_info, "Failed to connect to Database:error:%sn", Mysql_error (&mysql));
return 1;
}
else Syslog (log_user| Log_info, "Connect to Database:n");
Find_ps ();
Db_close ();
return 0;
}
int Db_close ()
{
Mysql_close (&mysql);
return 0;
}


int Find_ps ()
{
Mysql_row M_row;
Mysql_res *m_res;
Char sql[1024],username[32];
int Res=1;
int *id;
sprintf (SQL, "SELECT ID from username");
if (mysql_query (&mysql,sql)!= 0)
{
Syslog (log_user| Log_info, "Select Ps_info Error:%sn", Mysql_error (&mysql));
return res;
}
M_res = Mysql_store_result (&mysql);
if (m_res==null)
{
Syslog (log_user| Log_info, "Select username Error:%sn", Mysql_error (&mysql));
res = 3;
return res;
}
if (M_row = Mysql_fetch_row (m_res))
{
printf ("M_row=%dn", Atoi (m_row[0));
res = 0;
}
Mysql_free_result (M_res);
return res;
}

Compile command
Gcc-g Connect_db.c-l/usr/lib/mysql-lmysqlclient-lz
Attention:
If/tmp/cctgmms21.o:in function ' main ':
/TMP/CCTGMMS21.O (. text+0x11): Undefined reference to ' mysql_init '
Then the parameter increases-l/usr/lib/mysql-lmysqlclient
If
USR/LIB/MYSQL/LIBMYSQLCLIENT.A (MY_COMPRESS.O): in function ' my_uncompress ':
MY_COMPRESS.O (. Text+0xaa): Undefined reference to ' uncompress '
Then increase the-LZ parameter