Looping Through MySQL Query Results with PDO
Query with Parameter
When using PDO to query a database, you may encounter the need to execute queries with dynamic parameters. This allows you to easily query data based on user input or other runtime variables.
To loop through results with a parameter, use the following steps:
- Prepare a parameterized statement using the prepare() method. This places placeholders in the query where dynamic values will be substituted.
- Bind values to the placeholders using the bindValue() method.
- Execute the statement using the execute() method.
- Fetch the results using the fetch() method.
Example
<code class="php">$pdo = new PDO("mysql:host=localhost;dbname=test", "user", "password"); $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $stmt = $pdo->prepare("SELECT * FROM widgets WHERE something=:something"); $stmt->bindValue(":something", "something else"); $stmt->execute(); while ($results = $stmt->fetch(PDO::FETCH_ASSOC)) { echo $results["widget_name"]; }</code>
In this example, the $something placeholder in the query is bound using the bindValue() method, and the results are then fetched using the fetch() method within a loop.
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