Retrieving a Single Cell Value with PDO
When working with relational databases, it's common to retrieve specific data from selected columns within a row. In this case, the objective is to retrieve a single cell value from a MySQL table.
To execute this task, PHP's PDO (PHP Data Objects) extension provides a convenient method. Assuming you have the query:
SELECT some_col_name FROM table_name WHERE user=:user
where you need to extract the value in the some_col_name column, the following code can be used:
<code class="php">$stmt = $dbh->prepare("SELECT some_col_name FROM table_name WHERE user=:user");
$stmt->bindParam(':user', $user);
$stmt->execute();
$col_value = $stmt->fetchColumn();</code>
Here, $col_value will directly contain the value of the column for the row matching the user parameter.
It's worth noting that before executing the query, you must bind the :user parameter with the actual user value. If your query returns no rows (e.g., no matching user found), the fetchColumn() method will return false.
The above is the detailed content of How to Fetch a Single Cell Value Using PDO?. For more information, please follow other related articles on the PHP Chinese website!
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