Creating and reading from a table in the same SQL script - sql

Question

I am developing a SQL script in SQL Developer which will obfuscate personal data in a schema using Oracle SQL. The script looks into a table called "OBFUS_TABLE" which contains a list of which tables and columns need to be obfuscated and how. It then loops through the table, altering the data as it goes.
I have tested the actual loop and obfuscate process and it works fine, I have also successfully tested the beginning of the script up to just before the loop, which creates OBFUS_TABLE and inserts the values into it. The problem comes when it tries to do the two together, failing on a "table or view does not exist" error when it attempts to execute the loop. Snippet of code below:
alter session set current_schema = SYSTEM;
DECLARE
t_count NUMBER;
t_count2 NUMBER;
p_tname VARCHAR2(100);
p_cname VARCHAR2(100);
l_datatype VARCHAR2(100);
BEGIN
SELECT COUNT(*) INTO t_count FROM all_tables WHERE table_name = 'OBFUS_TABLE';
SELECT COUNT(*) INTO t_count2 FROM all_tables WHERE table_name = 'OBFUS_LOG';
IF (t_count = 0)
THEN
EXECUTE immediate 'create table OBFUS_TABLE( TABLENAME VARCHAR2(200 BYTE), COLUMNNAME VARCHAR2(200 BYTE), DATA_TYPE VARCHAR2(20 BYTE), ACTIVE VARCHAR(1 BYTE) )';
END IF;
IF (t_count2 = 0)
THEN
EXECUTE immediate 'CREATE TABLE OBFUS_LOG (SRC_TABLENAME VARCHAR2(50 BYTE), SRC_TABLE_ROW_COUNT NUMBER, COPY_TABLENAME VARCHAR2(50 BYTE), COPY_TABLE_ROW_COUNT NUMBER, UPDATE_DATE TIMESTAMP(6) )';
END IF;
EXECUTE immediate 'INSERT INTO OBFUS_TABLE VALUES (''OB_MYTABLE1'',''SRNM'',''NAME'',''Y'')';
COMMIT;
FOR x IN (SELECT TABLENAME, COLUMNNAME, DATA_TYPE FROM OBFUS_TABLE WHERE ACTIVE='Y')
LOOP
p_tname := upper(x.TABLENAME); -- Table name
p_cname := upper(x.COLUMNNAME); -- Column name
l_datatype := upper(x.DATA_TYPE);
dbms_output.put_line('Started: '||TO_CHAR(sysdate,'YYYY/MM/DD HH24:MI:SS'));
END LOOP;
END;
NB: There are actually around 30 insert statements in exactly the same format as the one above. I removed them since they would pad out this post too much, but I have manually checked every insert statement and they're all correct.
I assume the problem is that SQL Developer does a "sanity check" on the code before running, and looks ahead to the loop and realises OBFUS_TABLE doesn't exist, but fails to understand that by the time that piece of code is executed, OBFUS_TABLE will definitely exist.
Is there a way to get around this? I thought maybe a GOTO statement might help but no luck. I would rather keep the solution as one single script rather than two seperate ones, but if the only way around this is to do so then I could do that I suppose. Any help would be much appreciated.

Answer 1

You will need to use dynamic SQL for the select like this:
declare
...
l_tname varchar2(100);
l_cname varchar2(100);
l_datatype varchar2(100);
rc sys_refcursor;
begin
...
open rc for 'SELECT TABLENAME, COLUMNNAME, DATA_TYPE
FROM OBFUS_TABLE WHERE ACTIVE=''Y''';
loop
fetch rc into l_tname, l_cname, l_datatype;
exit when rc%notfound;
dbms_output.put_line('Started: '||TO_CHAR(sysdate,'YYYY/MM/DD HH24:MI:SS'));
end loop;
close rc;
end;