mysql_select_db

mysql_select_db changes the default database on an active connection; the current default can also be queried with the SELECT DATABASE() SQL function.

Syntax

int mysql_select_db(MYSQL * mysql,
                    const char * db);

Parameters

mysql - a mysql handle, which was previously allocated by mysql_init() or mysql_real_connect().
db - the default database name

Description

Selects a database as default.

Return Value

Returns zero on success, non-zero on failure.

To retrieve the name of the default database either execute the SQL command SELECT DATABASE() or retrieve the value via mariadb_get_infov() API function.

The default database can also be set by the db parameter in mysql_real_connect().

Examples

SQL

# switch to default database test
USE test;
# check default database
SELECT DATABASE();
+------------+
| database() |
+------------+
| test       |
+------------+

MariadDB Connector/C

static int set_default_db(MYSQL *mysql)
{
  int rc;
  char *default_db;

  /* change default database to test */
  rc= mysql_select_db(mysql, "test");
  if (rc)
    return rc;  /* Error */

  /* get the default database */
  rc= mariadb_get_infov(mysql, MARIADB_CONNECTION_SCHEMA, &default_db);
  if (rc)
    return rc; /* Error */

  if (strcmp("test", default_db) != NULL)
  {
    printf("Wrong default database\n");
    return 1;
  }
  printf("Default database: %s", default_db);
  return 0;
}