Myslím, že existují lepší způsoby, jak to implementovat na Oracle 10g/11g, ale mělo by to fungovat dobře na Oracle 9i nebo vyšší:
CREATE OR REPLACE PROCEDURE prc_file_mult_column_generate(
p_file_dir VARCHAR2, -- mandatory (Oracle directory name)
p_file_name VARCHAR2, -- mandatory
p_sql_query VARCHAR2, -- Multiple column SQL SELECT statement that needs to be executed and processed
p_delimiter CHAR -- column delimiter
)
AS
l_cursor_handle INTEGER;
l_dummy NUMBER;
l_col_cnt INTEGER;
l_rec_tab DBMS_SQL.DESC_TAB;
l_current_col NUMBER(16);
l_current_line VARCHAR2(2047);
l_column_value VARCHAR2(300);
l_file_handle UTL_FILE.FILE_TYPE;
l_print_text VARCHAR2(100);
l_record_count NUMBER(16) := 0;
BEGIN
/* Open file for append*/
l_file_handle := UTL_FILE.FOPEN(p_file_dir, p_file_name, 'a', 2047); --Append Mode, 2047 chars per line max, possibly increasable
l_cursor_handle := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(l_cursor_handle, p_sql_query, DBMS_SQL.native);
l_dummy := DBMS_SQL.EXECUTE(l_cursor_handle);
/* Output column names and define them for latter retrieval of data */
DBMS_SQL.DESCRIBE_COLUMNS(l_cursor_handle, l_col_cnt, l_rec_tab); -- get column names
/* Append to file column headers */
l_current_col := l_rec_tab.FIRST;
IF (l_current_col IS NOT NULL) THEN
LOOP
DBMS_SQL.DEFINE_COLUMN(l_cursor_handle, l_current_col, l_column_value, 300);
l_print_text := l_rec_tab(l_current_col).col_name || p_delimiter;
UTL_FILE.PUT (l_file_handle, l_print_text);
l_current_col := l_rec_tab.NEXT(l_current_col);
EXIT WHEN (l_current_col IS NULL);
END LOOP;
END IF;
UTL_FILE.PUT_LINE (l_file_handle,' ');
/* Append data for each row */
LOOP
EXIT WHEN DBMS_SQL.FETCH_ROWS(l_cursor_handle) = 0; -- no more rows to be fetched
l_current_line := '';
/* Append data for each column */
FOR l_current_col IN 1..l_col_cnt LOOP
DBMS_SQL.COLUMN_VALUE (l_cursor_handle, l_current_col, l_column_value);
l_print_text := l_column_value || p_delimiter;
l_current_line := l_current_line || l_column_value || p_delimiter;
END LOOP;
l_record_count := l_record_count + 1;
UTL_FILE.PUT_LINE (l_file_handle, l_current_line);
END LOOP;
UTL_FILE.FCLOSE (l_file_handle);
DBMS_SQL.CLOSE_CURSOR(l_cursor_handle);
EXCEPTION
WHEN OTHERS THEN
-- Release resources
IF DBMS_SQL.IS_OPEN(l_cursor_handle) THEN
DBMS_SQL.CLOSE_CURSOR(l_cursor_handle);
END IF;
IF UTL_FILE.IS_OPEN (l_file_handle) THEN
UTL_FILE.FCLOSE (l_file_handle);
END IF;
--RAISE ;
DBMS_OUTPUT.PUT_LINE(DBMS_UTILITY.format_error_stack);
END;
/