#include <mysql.h>
#include <stdio.h>
#include <stdlib.h>

#define NUM_CLIENTS 50

/*
create table n1 (id int primary key) engine=ndb;
insert into n1 values(1);

export LD_LIBRARY_PATH=/usr/local/mysql/lib
gcc -I/usr/local/mysql/include -L/usr/local/mysql/lib -lpthread -lmysqlclient bench.c
time ./a.out
*/

void* do_process(void* arg){
  MYSQL mysql;
  char *sql = "SELECT id FROM n1 WHERE id = 1";
  int i=0;
  MYSQL_RES   *result;
  unsigned int errno;
  char *error;
  int query_res;

  if ( !mysql_init(&mysql) ) {
    fprintf(stderr, "mysql_init failed\n");
    exit(-1);
  }
  if ( !mysql_real_connect(&mysql, "localhost", "root", "", "test",
                           3306, "/tmp/mysql.sock", 0) ){
    fprintf(stderr, "Failed to connect to database: Errno=%d, Error: %s," \
            "Connected=%d\n",
            mysql_errno(&mysql), mysql_error(&mysql), i);
    goto err2;
  }
  for(i=0; i< 2000; i++){
    query_res= mysql_query(&mysql, sql);
    if (query_res != 0) goto err;
    result = mysql_store_result(&mysql);
    mysql_free_result(result);
  }
  mysql_close(&mysql);
  return;

err:
  errno = mysql_errno(&mysql);
  error = (char*)mysql_error(&mysql);
  fprintf(stderr, "errno = %u, error = %s\n", errno, error);
  mysql_close(&mysql);
err2:
  return;
}


int main(int argc, char **argv)
{
  pthread_t   tid[NUM_CLIENTS];
  int i=0;

  for (i=0; i<NUM_CLIENTS; i++)
  {
    pthread_create(&tid[i], NULL, do_process, (void*)0);
  }

  for (i=0; i<NUM_CLIENTS; i++)
  {
    pthread_join(tid[i], NULL);
  }
  return 0;
}