Add setting into_outfile_create_parent_directories to automatically create parent

Why it matters

This feature solves the problem of INTO OUTFILE commands failing due to missing parent directories. It simplifies workflows where query results are written to nested or non-existing directory paths by automatically creating the necessary directories, improving usability and reliability.

How to use it

Enable the feature by setting into_outfile_create_parent_directories to 1 before running SELECT ... INTO OUTFILE 'path/to/file' queries. For example:

SET into_outfile_create_parent_directories = 1;
SELECT * FROM table INTO OUTFILE '/nested/dir/result.csv';