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【DM版本】:DM8
【操作系统】：WIN11
【CPU】:i710510U
【问题描述】*：
CREATE OR REPLACE PROCEDURE conf_apply_listInfo( "begintime" IN VARCHAR(32),
"endtime" IN VARCHAR(32),
"operatorId" IN int,
"states" IN int,
"beginIndex" IN int,
"endIndex" IN int,
"rowSum" out int)
AUTHID DEFINER
as

as
v_str varchar2(1000);
v_str_sum varchar2(1000);
v_strsql varchar2(1000);
rowSum1 int;
BEGIN

IF beginIndex > 0 THEN
	SET beginIndex := beginIndex - 1;
END IF;

-- 会议未审批数
IF states = 1 THEN
	
	SET v_str := CONCAT(SELECT * FROM conf WHERE create_time > '",begintime,"' 
													AND create_time < '",endtime,"'  
													AND appointmentState = 1
													AND auditState IS NULL
													AND applyPeople_Id IN ( SELECT id FROM operator WHERE dept_id IN ( SELECT dept_id FROM operator WHERE unitId = '",operatorId,"' ) ));

-- 会议通过数
ELSEIF states = 2 THEN
	
	SET v_str := CONCAT(SELECT * FROM conf WHERE create_time > '",begintime,"'
												AND create_time < '",endtime,"'  
												AND appointmentState = 1 
												AND auditState = 1 
												AND applyPeople_Id IN ( SELECT id FROM operator WHERE dept_id IN ( SELECT dept_id FROM operator WHERE unitId = '",operatorId,"' ) ));

-- 会议驳回数
ELSEIF states = 3 THEN

	SET v_str := CONCAT(SELECT * FROM conf WHERE create_time > '",begintime,"' 
												AND create_time < '",endtime,"' 
												AND appointmentState = 1 
												AND auditState = 2 
												AND applyPeople_Id IN ( SELECT id FROM operator WHERE dept_id IN ( SELECT dept_id FROM operator WHERE unitId = '",operatorId,"' ) ));

END IF;

SET v_str_sum := concat('select count(1) into rowSum1 from (', v_str ,') b');
-- PREPARE stmt1 FROM @v_strsql;
EXECUTE v_str_sum;
-- DEALLOCATE PREPARE v_str_sum;
SET rowSum:=rowsum1;

SET v_strsql := concat('select * from (', v_str ,') c limit ', beginIndex , ',', endIndex-beginIndex);
-- PREPARE stmt1 FROM @v_strsql;
EXECUTE v_strsql;
-- DEALLOCATE PREPARE stmt1;

END;

请问如何优化这个存储过程，问题1是select语句过长，达到可执行的效果

还有第二问题

CREATE OR REPLACE PROCEDURE conf_apply_statistics("begintime" IN VARCHAR(32), "endtime" IN VARCHAR(32), "operatorId" IN int)

as

BEGIN
SELECT
a1.count,
a2.agreecount,
a3.noagreecount,
a1.count - a2.agreecount - a3.noagreecount AS outcount
FROM
(
SELECT
IF( sum( 1 ) IS NULL, 0, sum( 1 ) ) AS count
FROM
conf
WHERE
create_time > begintime
AND create_time < endtime
AND appointmentState = 1
AND applyPeople_Id IN ( SELECT id FROM operator WHERE dept_id IN ( SELECT dept_id FROM operator WHERE unitId = operatorId ) )
) AS a1,
(
SELECT
IF( sum( 1 ) IS NULL, 0, sum( 1 ) ) AS agreecount
FROM
conf
WHERE
create_time > begintime
AND create_time < endtime
AND appointmentState = 1
AND auditState = 1
AND applyPeople_Id IN ( SELECT id FROM operator WHERE dept_id IN ( SELECT dept_id FROM operator WHERE unitId = operatorId ) )
) AS a2,
(
SELECT
IF( sum( 1 ) IS NULL, 0, sum( 1 ) ) AS noagreecount
FROM
conf
WHERE
create_time > begintime
AND create_time < endtime
AND appointmentState = 1
AND auditState = 2
AND applyPeople_Id IN ( SELECT id FROM operator WHERE dept_id IN ( SELECT dept_id FROM operator WHERE unitId = operatorId ) )
) AS a3 ;

-- PREPARE stmt from sql;
-- EXECUTE sql;
END;

这个IF判断我怎么替换，如果是Null就返回0，如果不是就返回查询出来的值。求教