Php/docs/mysqli.select-db
mysqli::select_db
mysqli_select_db
(PHP 5, PHP 7)
mysqli::select_db -- mysqli_select_db — Selects the default database for database queries
Description
Object oriented style
public mysqli::select_db
( string $dbname
) : bool
Procedural style
mysqli_select_db
( mysqli $link
, string $dbname
) : bool
Selects the default database to be used when performing queries against the database connection.
Note:
This function should only be used to change the default database for the connection. You can select the default database with 4th parameter in mysqli_connect().
Parameters
link- Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()
dbname- The database name.
Return Values
Returns TRUE on success or FALSE on failure.
Examples
Example #1 mysqli::select_db() example
Object oriented style
<?php$mysqli = new mysqli("localhost", "my_user", "my_password", "test");/* check connection */if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit();}/* return name of current default database */if ($result = $mysqli->query("SELECT DATABASE()")) { $row = $result->fetch_row(); printf("Default database is %s.\n", $row[0]); $result->close();}/* change db to world db */$mysqli->select_db("world");/* return name of current default database */if ($result = $mysqli->query("SELECT DATABASE()")) { $row = $result->fetch_row(); printf("Default database is %s.\n", $row[0]); $result->close();}$mysqli->close();?>
Procedural style
<?php$link = mysqli_connect("localhost", "my_user", "my_password", "test");/* check connection */if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit();}/* return name of current default database */if ($result = mysqli_query($link, "SELECT DATABASE()")) { $row = mysqli_fetch_row($result); printf("Default database is %s.\n", $row[0]); mysqli_free_result($result);}/* change db to world db */mysqli_select_db($link, "world");/* return name of current default database */if ($result = mysqli_query($link, "SELECT DATABASE()")) { $row = mysqli_fetch_row($result); printf("Default database is %s.\n", $row[0]); mysqli_free_result($result);}mysqli_close($link);?>
The above examples will output:
Default database is test. Default database is world.
See Also
- mysqli_connect() - Alias of mysqli::__construct
- mysqli_real_connect() - Opens a connection to a mysql server
