Server Utilities :: Compare Column Name Of Schema With Other Schema's Column Name

I have a standard schema named ABC and 600 more schema's over there in my database.They all has same table name and column name as on standard schema. But in some tables number of columns varying. So I need to compare all schemas with my standard schemas column name. I create below script but it is generating output in infinite loop.

SET SERVEROUTPUT ON
DECLARE
V_COLS VARCHAR2(20);

BEGIN
FOR CUR_CCD IN(SELECT DISTINCT TABLE_NAME,OWNER FROM ALL_TABLES
WHERE OWNER LIKE 'CCD_MAIN'
[code]....