maxdb_select_db

Selects the default database for database queries (PECL)
bool maxdb_select_db ( resource link, string dbname )

The maxdb_select_db() function selects the default database (specified by the dbname parameter) to be used when performing queries against the database connection represented by the link parameter.

注意:

This function should only be used to change the default database for the connection. You can select the default database with 4th parameter in maxdb_connect().

Return values

如果成功则返回 TRUE,失败则返回 FALSE

Example

例 1045. Object oriented style

<?php
$maxdb
= new maxdb("localhost", "MONA", "RED", "DEMODB");

/* check connection */
if (maxdb_connect_errno()) {
 
printf("Connect failed: %s\n", maxdb_connect_error());
  exit();
}

/* return name of current default database */
if ($result = $maxdb->query("SELECT SERVERDB FROM USERS WHERE USERNAME='MONA'")) {
 
$row = $result->fetch_row();
 
printf("Default database is %s.\n", $row[0]);
 
$result->close();
}

/* change db to non existing db */
$maxdb->select_db("XXXXXXXX");

/* return name of current default database */
if ($result = $maxdb->query("SELECT SERVERDB FROM USERS WHERE USERNAME='MONA'")) {
 
$row = $result->fetch_row();
 
printf("Default database is %s.\n", $row[0]);
 
$result->close();
}

$maxdb->close();
?>

例 1046. Procedural style

<?php
$link
= maxdb_connect("localhost", "MONA", "RED", "DEMODB");

/* check connection */
if (maxdb_connect_errno()) {
 
printf("Connect failed: %s\n", maxdb_connect_error());
  exit();
}

/* return name of current default database */
if ($result = maxdb_query($link, "SELECT SERVERDB FROM USERS WHERE USERNAME='MONA'")) {
 
$row = maxdb_fetch_row($result);
 
printf("Default database is %s.\n", $row[0]);
 
maxdb_free_result($result);
}

/* change db to non existing db */
maxdb_select_db($link, "XXXXXXXX");

/* return name of current default database */
if ($result = maxdb_query($link, "SELECT SERVERDB FROM USERS WHERE USERNAME='MONA'")) {
 
$row = maxdb_fetch_row($result);
 
printf("Default database is %s.\n", $row[0]);
 
maxdb_free_result($result);
}

maxdb_close($link);
?>

The above examples would produce the following output:

Default database is <...>.

Warning: maxdb_select_db(): -10709 Connection failed (RTE:database not running) <...>

Warning: maxdb_query(): -10821 Session not connected [] <...>

Warning: maxdb_close(): -10821 Session not connected [] <...>