code goes into infinite loop when updating table's column - sql

Question

expert.
I'm new to PLSQL programming.
More than 200 tables have 'EXAMPLE' columns.
I want to update the column 'EXAMPLE' with 'YES'.
The purpose of the following code is to update the 'EXAMPLE' column for every 10000 records.
But I think the following code enters an infinite loop.
Where am I making a mistake?.
how can i fix this?
declare
v_match_count integer;
table_name varchar2(30);
begin
v_match_count:=0;
for tablolar in
(
SELECT table_name
FROM user_tab_columns,user_objects
WHERE
user_tab_columns.table_name=user_objects.object_name and user_objects.object_type not in ('VIEW') AND
column_name IN ( 'FILE_NO', 'PROT_NO' )
GROUP BY table_name
HAVING Count(*) > 1
) loop
begin
-- v_match_count:=v_match_count+1;
-- dbms_output.put_line(tablolar.table_name||' = '||v_match_count);
WHILE TRUE LOOP
IF tablolar.table_name||'.EXAMPLE' IS NOT NULL THEN --the line I changed in the code.
--dbms_output.put_line(tablolar.table_name||' = '||v_match_count||' girdi.');
execute immediate 'UPDATE HASTANE.'||tablolar.table_name|| ' SET EXAMPLE=''YES'' WHERE '||tablolar.table_name||'.EXAMPLE IS NULL AND ROWNUM<10000' ;
COMMIT;
END IF;
IF tablolar.table_name||'.EXAMPLE' IS NULL THEN --the line I changed in the code.
EXIT;
end if;
-- v_match_count:=v_match_count+1;
END LOOP;
v_match_count:=v_match_count+1;
dbms_output.put_line(tablolar.table_name||' = '||v_match_count);
end;
end loop;
end;

Answer 1

In the test for 'EXAMPLE' the value will never be NULL so you will never exit the loop. Try checking for the existence of the column 'EXAMPLE' in your query, then you can just do the update for each table and the loop will exit when all the records are read.
declare
v_match_count integer;
v_record_count INTEGER;
table_name varchar2(30);
begin
v_match_count:=0;
v_record_count := 0;
for tablolar in
(
SELECT table_name
FROM user_tab_columns,user_objects
WHERE
user_tab_columns.table_name=user_objects.object_name and user_objects.object_type not in ('VIEW') AND
column_name IN ( 'FILE_NO', 'PROT_NO' )
AND EXISTS (SELECT * FROM user_tab_columns x
WHERE x.table_name = user_tab_columns.table_name AND x.column_name = 'EXAMPLE')
GROUP BY table_name
HAVING Count(*) > 1
) loop
BEGIN
--- Get the record cound
execute immediate 'SELECT COUNT(*) FROM ' || 'HASTANE.' ||tablolar.table_name || ' WHERE '||tablolar.table_name||'.EXAMPLE IS NULL'
INTO v_record_count;
--- Do we have anything to update?
IF NVL(v_record_count,0) > 0 THEN
--- Update all the records that are NULL
FOR v_match_count IN 1..v_record_count LOOP
execute immediate 'UPDATE HASTANE.'||tablolar.table_name|| ' SET EXAMPLE=''YES'' WHERE '||tablolar.table_name||'.EXAMPLE IS NULL' ;
--- Check if it's time to COMMIT (every 10000 records)
IF MOD(v_match_count, 10000) = 0 THEN
COMMIT;
END IF;
END LOOP;
--- COMMIT remaining records since last COMMIT
COMMIT;
END IF;
end;
end loop;
end;