stmtsetFetchModePDOFETCHNUM

The function `stmtsetFetchMode` is a method used in PHP's PDO (PHP Data Objects) extension to configure how data is fetched from a database when executing a prepared statement. PDO provides a uniform interface for interacting with databases, and this method allows developers to specify the SQL types for bound parameters and fetched data.

When working with PDO prepared statements, developers often need to ensure that data types are correctly handled between PHP variables and database columns. The `stmtsetFetchMode` method sets the default fetch style for subsequent calls to `fetch` on the statement object. The fetch style determines how data is retrieved from the database, particularly in terms of data type handling.

The primary use case for `stmtsetFetchMode` is to define whether PDO should return rows as associative arrays, indexed arrays, or objects. For example, calling `stmtsetFetchMode(PDO::FETCH_ASSOC)` ensures that each row is returned as an associative array where keys are column names and values are the corresponding data. Similarly, `PDO::FETCH_OBJ` returns rows as objects with properties matching column names, while `PDO::FETCH_BOTH` combines both associative and indexed arrays.

Additionally, `stmtsetFetchMode` can be used to specify the SQL types for bound parameters, ensuring consistency between PHP variables and database columns. This is particularly useful when dealing with large objects or binary data, where explicit type handling prevents unexpected behavior.

The method is called on a PDOStatement object, which is obtained after executing a prepared statement. It is important to note that `stmtsetFetchMode` only affects subsequent fetch operations on the same statement. If multiple fetch styles are required, they can be set individually for each fetch call using the `fetch` method's optional parameter.

This function is part of PDO's flexibility, allowing developers to tailor data retrieval to their application's needs while maintaining compatibility across different database systems.