Error using Oracle Ref Cursor - sql

Question

I'm trying to do something fairly simple, I am trying to automate the removal and back up of tables from my personal table space. I have about 100 tables and want to get rid of all of them (except a table that I'm using to store the table names), but want to keep the data from the tables in case I need them sometime in the future. Below is the code I am trying to use to accomplish this. I am getting an error on the ref cursor, which I'll include below my code. I half expect somebody to tell me I'm an idiot and explain an easier way to do this. If not, please tell me what I'm doing wrong with the way that I am doing it, thanks.
DECLARE
v_folder_name VARCHAR2(100) := 'MY_FOLDER';
TYPE QRY_CURSOR IS REF CURSOR;
v_qry_cursor QRY_CURSOR;
v_file_name VARCHAR2(320);
v_file sys.utl_file.file_type;
v_max_buffer_length CONSTANT BINARY_INTEGER := 32767;
v_qry_str VARCHAR2(4000); --I've tried this with 32767, made no difference
v_drop_string VARCHAR2(4000);
v_dynamic_record VARCHAR2(4000); --tried this with 32767 also
CURSOR GET_TABLE_NAMES IS
SELECT * FROM TEMP_BACKUP_TABLE WHERE TABLE_NAME <> 'TEMP_BACKUP_TABLE';
FUNCTION startFile(file_name VARCHAR2)
--working function, used with many procedures, left out for brevity
END startFile;
FUNCTION closeFile(file_name VARCHAR2)
--working function, used with many procedures, left out for brevity
END closeFile;
BEGIN
INSERT INTO TEMP_BACKUP_TABLE SELECT DISTINCT TABLE_NAME FROM ALL_TAB_COLS WHERE OWNER = 'ME';
COMMIT;
FOR REC IN GET_TABLE_NAMES LOOP
v_file_name := REC.TABLE_NAME;
v_file := startFile(v_file_name);
v_qry_str := 'SELECT * FROM ' || v_file_name;
v_drop_string := 'DROP TABLE ' || v_file_name;
OPEN v_qry_cursor FOR v_qry_str; -- this is the line that returns an error
LOOP
FETCH v_qry_cursor INTO v_dynamic_record;
EXIT WHEN v_qry_cursor%NOTFOUND;
sys.utl_file.put_line(v_file, v_dynamic_record);
END LOOP;
CLOSE v_qry_cursor;
EXECUTE IMMEDIATE v_drop_string;
COMMIT;
v_file := closeFile(v_file_name);
END LOOP;
DELETE FROM TEMP_BACKUP_TABLE;
END;
The error I'm getting is as follows:
Error report:
ORA-00932: inconsistent datatypes: expected - got -
ORA-06512: at line 73
00932. 00000 - "inconsistent datatypes: expected %s got %s"
*cause:
*action:
Thanks for any help.

Answer 1

At a minimum, utl_file.put_line does not take arbitrary record and you can't fetch an arbitrary list of columns into a varchar2.
You could iterate over each column and construct a SQL statement that concatenates the values from each column into a single string. That would include doing things like putting a to_char with an explicit format mask on your date or timestamp columns, adding a delimiter, escaping any delimiters that exist in your data, etc. This is generally a rather tedious and error-prone process. And then you'll need to write a SQL*Loader control file to load the data back in the future.
It sounds like you'd be better off exporting the table using the Oracle export utility. That's a command-line utility (exp or expdp depending on whether you want to use the classic version or the DataPump version) that lets you export the table definition and data to a file that you can load later using the Oracle import utility.