Buffers the complete result set for a prepared SELECT on the client.
The objective is to understand the behavior and operational limits, not only the method name.
What It Does
Buffers the complete result set for a prepared SELECT on the client.
Syntax and Return Value
mysqli_stmt::store_result(...)The return value and exceptional cases depend on the call described here: Buffering uses memory and cannot be combined with get_result on that execution.
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->store_result();
echo "Buffered rows: " . $stmt->num_rows;
$stmt->free_result();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->store_result();
echo "Buffered rows: " . $stmt->num_rows;
$stmt->free_result();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->store_result();
echo "Buffered rows: " . $stmt->num_rows;
$stmt->free_result();Important Behavior and Edge Cases
Buffering uses memory and cannot be combined with get_result on that execution.
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::store_result | Buffers the complete result set for a prepared SELECT on the client. |
| Related API / pattern | fetch without buffering can be more memory efficient for large result sets. |
Common Beginner Mistakes
| Mistake | Correct approach |
|---|---|
| Assuming the happy path covers edge cases | Buffering uses memory and cannot be combined with get_result on that execution. |
| Using a related API interchangeably | fetch without buffering can be more memory efficient for large result sets. |
Key Takeaways
- Buffers the complete result set for a prepared SELECT on the client.
- Buffering uses memory and cannot be combined with get_result on that execution.
- fetch without buffering can be more memory efficient for large result sets.
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.