MySQL Stored Procedure Unexpected Behaviour in certain conditions - mysql

Question

I am relatively new to MySQL stored Procedures. I have a stored procedure that works fine in certain conditions and not in other. I'm a bit confused that what causes the error. It is a entity processing SP, based on certain values and conditions it either creates or update entity from data in a staging table.
In conditions when it works fine:
When I only process a single entity.
Works for bulk entries when there is nothing in entity table.
Don't works when:
There are entries in entity table and bulk processing is done. - Error in checking up the already existing entity_id in entity and older entity_id is assigned instead a new one should be created.
(I actually need above scenario to work more frequently than others)
I have tried to keep the code to minimum in order to understand the flow of SP. Please consider all variables as declared. SP might not compile.
CREATE DEFINER=`admin`#`%` PROCEDURE `sp_ent`(test_id int)
BEGIN
-- Move code tables to temp tables
-- Declare all the required variables here
DECLARE counter, len INT;
DECLARE var2 INT;
DECLARE var3 TINYINT(1);
DECLARE var4 DECIMAL(18,4);
DECLARE var5 DATE;
DECLARE var6 VARCHAR(1000);
DECLARE var7 VARCHAR(5000);
DROP TEMPORARY TABLE IF EXISTS `temp_ent`;
IF test_id IS NOT NULL THEN
CREATE TEMPORARY TABLE IF NOT EXISTS `temp_ent` AS (SELECT * FROM `ent_st` WHERE processed = 0 and id=test_id);
ELSE
CREATE TEMPORARY TABLE IF NOT EXISTS `temp_ent` AS (SELECT * FROM `ent_st` WHERE processed = 0);
END IF;
ALTER TABLE `temp_ent` ADD PRIMARY KEY(id);
-- SELECT * FROM `temp_ent`;
DROP TEMPORARY TABLE IF EXISTS `temp_exc`; CREATE TEMPORARY TABLE IF NOT EXISTS `temp_exc` AS (SELECT * FROM `code_exc`);
-- A few more like above
SET counter=1, len=(SELECT COUNT(*) FROM `temp_ent`);
WHILE counter <= len DO
SELECT `id`,var1, var2, var3
INTO v_id,var1, var2, var3
FROM `temp_ent` LIMIT 1;-- WHERE `id` = v_id;
BEGIN
DECLARE insufficient_information CONDITION FOR SQLSTATE '45000';
DECLARE CONTINUE HANDLER FOR insufficient_information SET v_proccessed=1;
SET v_status = CASE
WHEN ... THEN ...
ELSE 'valid'
END;
IF v_status <> 'valid' THEN SIGNAL insufficient_information; END IF;
SELECT `entity_id`,`entity`
INTO v_underlying_entity_id,v_underlying_entity_symbol
FROM `entity` WHERE `entity_id` = v_underlying OR `entity` = v_underlying_entity;
SET v_underlying_entity_symbol = COALESCE(v_underlying_entity_symbol,v_underlying_entity);
SET v_entity = (
CASE
WHEN ... THEN ...
WHEN ... THEN ...
.
.
WHEN ... THEN ...
END
);
SELECT `entity_id`,`entity`
INTO v_entity_id_check,v_entity_check
FROM entity WHERE `entity`=v_entity and `exc`=v_exc;
-- SELECT v_entity_id_check,v_entity_check,v_entity,v_exc;
IF v_entity_check IS NULL THEN
-- SELECT 'Create New Entity and Add';
SET v_entity_id = COALESCE((SELECT MAX(`entity_id`) FROM entity),0) + 1;
SET new_entity = 1;
ELSE
-- SELECT 'Entity Already Present';
SET v_entity_id = v_entity_id_check;
SET new_entity = 0;
END IF;
-- SELECT v_entity_id, v_entity, new_entity;
SET v_name = UPPER(COALESCE(v_name,v_entity));
-- UPDATE entity and underlying/derivatives table
IF new_entity = 1 THEN
-- Insert in respective tables
IF ... THEN
-- SELECT 'Entity Added',v_entity; -- Underlying Entity
INSERT INTO `entity_underlying` (`entity_id`,`entity`,`name`,`exc`,`seg`,`ins`,`isin`,`fo_yn`,`tick`,`lot_size`,`active_yn`)
VALUES (v_entity_id,v_entity,v_name,v_exc,v_seg,v_ins,COALESCE(v_isin,''),COALESCE(v_fo_yn,0),COALESCE(v_tick,0.05),COALESCE(v_lot_size,1),1);
ELSEIF ... THEN
-- SELECT 'Entity Added',v_entity; -- Derivative Entity
INSERT INTO `entity_derivatives` (`entity_id`,`entity`,`name`,`underlying`,`exc`,`seg`,`ins`,`ser`,`isin`,`strike`,`tick`,`lot_size`,`expiry`,`ex_ty`,`active_yn`)
VALUES (v_entity_id,v_entity,v_name,COALESCE(v_underlying_entity_id,-1),v_exc,v_seg,v_ins,COALESCE(v_ser,''),v_isin,COALESCE(v_strike),COALESCE(v_tick,0.05),COALESCE(v_lot_size,-1),v_expiry,v_ex_ty,1);
END IF;
-- Insert in final table
INSERT INTO entity(`entity_id`,`entity`,`exc`,`active_yn`)
VALUES (v_entity_id,v_entity,v_exc,1);
SET v_status='Entity Added';
ELSE
SET v_status='Not a New Entity';
END IF;
END;
UPDATE `ent_st` SET `entity_id`=v_entity_id,`processed`=1,`status`=v_status WHERE id=v_id;
DELETE FROM `temp_ent` WHERE id=v_id;
SET counter = counter +1;
COMMIT;
END WHILE;
END
Any help is highly appreciated. Thanks in advance.