Description:
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The mysqli functions fetch_field, fetch_fields and fetch_field_direct do not return the db name when the C API allows it.  For the past several versions I have been adding the following code to mysqli_api.c to include this field.  Could this be included in future releases?

mysqli_fetch_field function
add_property_string(return_value, "db",(field->db ? field->db : ""), 1);

mysqli_fetch_fields function
add_property_string(obj, "db",(field->db ? field->db : ""), 1);

mysqli_fetch_field_direct
add_property_string(return_value, "db",(field->db ? field->db : ""), 1);