


Selecting Multiple Rows from MySQL and Accessing Them in PHP
Question:
How can I select multiple rows from a MySQL database using a single query and retrieve them in a PHP array with a multidimensional structure?
Answer:
To retrieve multiple rows from MySQL and access them in PHP through a multidimensional array, you can utilize the iterative nature of the mysql_fetch_assoc() function.
Solution:
- Establish MySQL Connection: Connect to your MySQL database using the mysql_connect() or mysqli_connect() function.
- Execute SQL Query: Run your SQL query that selects the desired rows from the database. The result of the query is stored in a result set.
- Loop Through Rows: To access multiple rows, you need to loop through the result set using while or foreach loops.
- Fetch Each Row: Inside the loop, call mysql_fetch_assoc() repeatedly to retrieve the current row as an associative array. Each call to mysql_fetch_assoc() returns the next row in the result set.
- Build Multidimensional Array: As you fetch each row, store it in a multidimensional array. For instance, you could create an array with the first dimension being the row number and the second dimension being the column names.
Example Code:
<code class="php"><?php // Connect to MySQL $connection = mysql_connect('host', 'username', 'password'); mysql_select_db('database', $connection); // Execute SQL Query $query = "SELECT * FROM table_name WHERE number1 = 1"; $result = mysql_query($query); // Loop Through Rows and Build Array $multidimensionalArray = array(); $i = 0; while ($row = mysql_fetch_assoc($result)) { $multidimensionalArray[$i] = $row; $i++; } // Access Row Data echo $multidimensionalArray[1]['number2']; ?></code>
By utilizing this approach, you can retrieve multiple rows from a MySQL database and access their data in a multidimensional PHP array.
The above is the detailed content of How to retrieve multiple rows from a MySQL database and access them in a PHP array with a multidimensional structure?. For more information, please follow other related articles on the PHP Chinese website!

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