3.8.46 mysqli::select_db, mysqli_select_db

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• mysqli::select_db

  mysqli_select_db

  Selects the default database for database queries

Description

Object-oriented style

public bool mysqli::select_db(string database);

Procedural style

bool mysqli_select_db(mysqli mysql,
                      string database);

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

mysql

Procedural style only: A mysqli object returned by mysqli_connect or mysqli_init

database

The database name.

Return Values

Returns true on success or false on failure.

Examples

Example 3.63 mysqli::select_db example

Object-oriented style

<?php

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");

/* get the name of the current default database */
$result = $mysqli->query("SELECT DATABASE()");
$row = $result->fetch_row();
printf("Default database is %s.\n", $row[0]);

/* change default database to "world" */
$mysqli->select_db("world");

/* get the name of the current default database */
$result = $mysqli->query("SELECT DATABASE()");
$row = $result->fetch_row();
printf("Default database is %s.\n", $row[0]);

Procedural style

<?php

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$link = mysqli_connect("localhost", "my_user", "my_password", "test");

/* get the name of the current default database */
$result = mysqli_query($link, "SELECT DATABASE()");
$row = mysqli_fetch_row($result);
printf("Default database is %s.\n", $row[0]);

/* change default database to "world" */
mysqli_select_db($link, "world");

/* get the name of the current default database */
$result = mysqli_query($link, "SELECT DATABASE()");
$row = mysqli_fetch_row($result);
printf("Default database is %s.\n", $row[0]);

The above examples will output:

Default database is test.
Default database is world.

See Also

mysqli_connect

mysqli_real_connect