Fetches the next prepared-statement result row into variables bound with bind_result.
The objective is to understand the behavior and operational limits, not only the method name.
What It Does
Fetches the next prepared-statement result row into variables bound with bind_result.
Syntax and Return Value
mysqli_stmt::fetch(...)The return value and exceptional cases depend on the call described here: A successful row yields true, while end-of-data returns null; errors can return false.
Requirements: install and enable the corresponding PHP driver or extension and configure the service before running the examples.
Example 1: Basic Use
The SELECT assumes users(id,email) in an actual MySQL database; output depends on its rows.
<?php
$host = getenv('DB_HOST'); $user = getenv('DB_USER'); $password = getenv('DB_PASSWORD'); $database = getenv('DB_NAME');
if (!$host || !$user || $password === false || !$database) throw new RuntimeException('Missing database configuration');
$mysqli = new mysqli($host, $user, $password, $database);
$mysqli->set_charset('utf8mb4');
$userId = 3;
$stmt = $mysqli->prepare("SELECT id, email FROM users WHERE id >= ? ORDER BY id");
$stmt->bind_param("i", $userId);
$stmt->execute();
$stmt->bind_result($id, $email);
while ($stmt->fetch()) echo $email . PHP_EOL;Example 2: A Second Scenario
The SELECT assumes users(id,email) in an actual MySQL database; output depends on its rows.
<?php
$host = getenv('DB_HOST'); $user = getenv('DB_USER'); $password = getenv('DB_PASSWORD'); $database = getenv('DB_NAME');
if (!$host || !$user || $password === false || !$database) throw new RuntimeException('Missing database configuration');
$mysqli = new mysqli($host, $user, $password, $database);
$mysqli->set_charset('utf8mb4');
$userId = 5;
$stmt = $mysqli->prepare("SELECT id, email FROM users WHERE id >= ? ORDER BY id");
$stmt->bind_param("i", $userId);
$stmt->execute();
$stmt->bind_result($id, $email);
while ($stmt->fetch()) echo $email . PHP_EOL;Example 3: Practical Checks
The SELECT assumes users(id,email) in an actual MySQL database; output depends on its rows.
<?php
$host = getenv('DB_HOST'); $user = getenv('DB_USER'); $password = getenv('DB_PASSWORD'); $database = getenv('DB_NAME');
if (!$host || !$user || $password === false || !$database) throw new RuntimeException('Missing database configuration');
$mysqli = new mysqli($host, $user, $password, $database);
$mysqli->set_charset('utf8mb4');
$userId = 8;
$stmt = $mysqli->prepare("SELECT id, email FROM users WHERE id >= ? ORDER BY id");
$stmt->bind_param("i", $userId);
$stmt->execute();
$stmt->bind_result($id, $email);
while ($stmt->fetch()) echo $email . PHP_EOL;Important Behavior and Edge Cases
A successful row yields true, while end-of-data returns null; errors can return false.
For production use, also account for error handling, data validation, resource limits and environment-specific driver behavior.
Comparison with Related Approaches
| Approach | Important distinction |
|---|---|
| mysqli_stmt::fetch | Fetches the next prepared-statement result row into variables bound with bind_result. |
| Related API / pattern | get_result returns a result object and supports fetch_assoc when mysqlnd is available. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Assuming the happy path covers edge cases | A successful row yields true, while end-of-data returns null; errors can return false. |
| Using a related API interchangeably | get_result returns a result object and supports fetch_assoc when mysqlnd is available. |
Key Takeaways
- Fetches the next prepared-statement result row into variables bound with bind_result.
- A successful row yields true, while end-of-data returns null; errors can return false.
- get_result returns a result object and supports fetch_assoc when mysqlnd is available.
Choose this API or pattern when its exact semantics match your task, and verify the result against the database driver and runtime used by your application.