How to Properly Use LIMIT in MySQL Prepared Statements with PHP?

LIMIT Keyword on MySQL with Prepared Statement

When attempting to use the LIMIT keyword in a prepared statement with MySQL, unexpected behavior can occur, such as parse errors when using strings as parameters. This issue arises due to PHP's PDO treating all parameters as strings by default during execution.

In your provided query:

SELECT id, content, date
FROM comment
WHERE post = ?
ORDER BY date DESC
LIMIT ?, ?

The values for the LIMIT parameters are being inserted as strings, resulting in an invalid SQL syntax:

LIMIT '0', '10'

To resolve this issue, you have several options:

Bind Parameters with Type

Bind the LIMIT parameters individually, specifying their data types:

$comments->bindParam(2, $min, PDO::PARAM_INT);
$comments->bindParam(3, $min, PDO::PARAM_INT);

Pass Parameters Outside the Prepared Statement

Avoid using parameters for the LIMIT values and embed them directly into the query:

$query = sprintf('SELECT id, content, date
    FROM comment
    WHERE post = ?
    ORDER BY date DESC
    LIMIT %d, %d', $min, $max);

Disable Emulated Prepares

Some drivers emulate prepared statements and may automatically quote numeric arguments. Disable this behavior:

$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, FALSE);

By implementing one of these approaches, you can correctly use the LIMIT keyword in prepared statements within MySQL.

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