PHP where statement
PHP MySQL Where clause
The WHERE clause is used to filter records.
WHERE clause
The WHERE clause is used to extract records that meet the specified criteria.
Syntax
SELECT column_name(s) FROM table_name
WHERE column_name operator value
To select data matching the specified conditions, please add to the SELECT statement WHERE clause.
The following operators can be used with the WHERE clause:
In order for PHP to execute the above statement, we must use mysqli_query() function. This function is used to send a query or command to the MySQL connection.
Example
The following example will select all rows with FirstName='Peter' from the "Persons" table:
<?php
$con=mysqli_connect("localhost","username","password","database");
// 检测连接
if (mysqli_connect_errno())
{
echo "连接失败: " . mysqli_connect_error();
}
$result = mysqli_query($con,"SELECT * FROM Persons
WHERE FirstName='Peter'");
while($row = mysqli_fetch_array($result))
{
echo $row['FirstName'] . " " . $row['LastName'];
echo "<br>";
}
?>The above code will output:
Peter Griffin
<?php
$con=mysqli_connect("localhost","username","password","database");
// 检测连接
if (mysqli_connect_errno())
{
echo "连接失败: " . mysqli_connect_error();
}
$result = mysqli_query($con,"SELECT * FROM Persons
WHERE FirstName='Peter'");
while($row = mysqli_fetch_array($result))
{
echo $row['FirstName'] . " " . $row['LastName'];
echo "<br>";
}
?>
