Bulk Insert (Row-wise Binding)

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The following example uses indicator variables and row-wise binding to insert an array of structures.

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

static void show_mysql_error(MYSQL *mysql)
{
  printf("Error(%d) [%s] \"%s\"", mysql_errno(mysql),
                                  mysql_sqlstate(mysql),
                                  mysql_error(mysql));
  exit(-1);
}

static void show_stmt_error(MYSQL_STMT *stmt)
{
  printf("Error(%d) [%s] \"%s\"", mysql_stmt_errno(stmt),
                                  mysql_stmt_sqlstate(stmt),
                                  mysql_stmt_error(stmt));
  exit(-1);
}

int main(int argc, char *argv[])
{
  MYSQL *mysql;
  MYSQL_STMT *stmt;
  MYSQL_BIND bind[3];

  struct st_data {
    unsigned long id;
    char id_ind;
    char forename[30];
    char forename_ind;
    char surname[30];
    char surname_ind;
  };

  struct st_data data[]= {
    {0, STMT_INDICATOR_NULL, "Monty", STMT_INDICATOR_NTS, "Widenius", STMT_INDICATOR_NTS},
    {0, STMT_INDICATOR_NULL, "David", STMT_INDICATOR_NTS, "Axmark", STMT_INDICATOR_NTS},
    {0, STMT_INDICATOR_NULL, "default", STMT_INDICATOR_DEFAULT, "N.N.", STMT_INDICATOR_NTS},
  };

  unsigned int array_size= 3;
  size_t row_size= sizeof(struct st_data);

  mysql= mysql_init(NULL);

  /* connect to MariaDB server */
  if (!mysql_real_connect(mysql, "localhost", "example", "example_pw", 
                          "example_db", 0, "/tmp/mysql.sock", 0))
    show_mysql_error(mysql);

  if (mysql_query(mysql, "DROP TABLE IF EXISTS bulk_example2"))
    show_mysql_error(mysql);

  if (mysql_query(mysql, "CREATE TABLE bulk_example2 (id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,"\
                         "forename CHAR(30) NOT NULL DEFAULT 'unknown', surname CHAR(30))"))
    show_mysql_error(mysql);

  stmt= mysql_stmt_init(mysql);
  if (mysql_stmt_prepare(stmt, "INSERT INTO bulk_example2 VALUES (?,?,?)", -1))
    show_stmt_error(stmt);

  memset(bind, 0, sizeof(MYSQL_BIND) * 3);

  /* We autogenerate id's, so all indicators are STMT_INDICATOR_NULL */
  bind[0].u.indicator= &data[0].id_ind;
  bind[0].buffer_type= MYSQL_TYPE_LONG;

  bind[1].buffer= &data[0].forename;
  bind[1].buffer_type= MYSQL_TYPE_STRING;
  bind[1].u.indicator= &data[0].forename_ind;

  bind[2].buffer_type= MYSQL_TYPE_STRING;
  bind[2].buffer= &data[0].surname;
  bind[2].u.indicator= &data[0].surname_ind;

  /* set array size */
  mysql_stmt_attr_set(stmt, STMT_ATTR_ARRAY_SIZE, &array_size);

  /* set row size */
  mysql_stmt_attr_set(stmt, STMT_ATTR_ROW_SIZE, &row_size);

  /* bind parameter */
  mysql_stmt_bind_param(stmt, bind);

  /* execute */
  if (mysql_stmt_execute(stmt))
    show_stmt_error(stmt);

  mysql_stmt_close(stmt);
  mysql_close(mysql);
}

Now we can check the content of table bulk_example2:

MariaDB [example_db]> select id,forename,surname from bulk_example2;
+----+----------+----------+
| id | forename | surname  |
+----+----------+----------+
|  1 | Monty    | Widenius |
|  2 | David    | Axmark   |
|  3 | unknown  | N.N.     |
+----+----------+----------+

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