sql.py: DbConn._db(): search_path: Don't append the existing search_path, because it usually includes the public schema, which is now different from the schema being imported into. This fixes a bug where sql.function_exists() would find public-schema functions in both the public schema and the import's schema because both were in the search_path, causing a DuplicateException "more than one function named ...". Note that the elements of the existing search_path are no longer needed now that vegbien_dest's $schemas includes $public. Also note that if an instance of DbConn does not specify the schemas param, the existing search_path will be left as-is rather than overwritten with an empty list.
sql.py: DbConn._db(): search_path: Don't append the existing search_path, because it usually includes the public schema, which is now different from the schema being imported into. This fixes a bug where sql.function_exists() would find public-schema functions in both the public schema and the import's schema because both were in the search_path, causing a DuplicateException "more than one function named ...". Note that the elements of the existing search_path are no longer needed now that vegbien_dest's $schemas includes $public. Also note that if an instance of DbConn does not specify the schemas param, the existing search_path will be left as-is rather than overwritten with an empty list.