SELECT后面有自定义函数的优化方法
Posted robinson1988
tags:
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又是EBS，一个SQL有700多行，要跑2个多小时，EBS开发请求帮忙优化
因为SQL太长，将其做了简化处理，简化后的SQL文本如下：
INSERT INTO nso_allocaton_fr_tmp
(create_date,
request_id,
c1,
c2,
c3,
c4,
c5,
c6,
c7,
c8,
c9,
c10,
c11,
c12,
c13,
c14,
c15,
c16,
c17,
c18,
c19,
c20,
c21,
c22,
c23,
c24,
c25,
c26,
c27,
c28,
c29,
c30,
c31,
c32,
c33,
c34,
c35,
c36,
c37,
c38,
c39,
c40,
c41,
c42,
c43,
c44,
c45,
c46,
c47,
c48,
c49,
c50,
c51,
c52,
c53,
c54,
c55,
c56,
c57,
c58,
c59,
c60,
c61,
c62,
c63,
c64,
c65,
c66,
c67,
c68,
c70)
(SELECT SYSDATE,
fnd_global.conc_request_id,
t.ou_name,
t.ou_name,
t.department_name,
t.sales_person,
t.project_number,
t.item_category,
(SELECT ffv.description
FROM fnd_flex_value_sets ffvs, fnd_flex_values_vl ffv
WHERE ffvs.flex_value_set_id = ffv.flex_value_set_id
AND ffvs.flex_value_set_name = 'XY_COA_PD'
AND ffv.flex_value = t.item_category
AND ffv.enabled_flag = 'Y'
AND nvl(ffv.start_date_active, trunc(SYSDATE)) <=
trunc(SYSDATE)
AND nvl(ffv.end_date_active, trunc(SYSDATE)) >= trunc(SYSDATE)
AND rownum = 1) item_category_desc,
t.item_type,
t.trade_mode,
t.po_type,
t.so_area,
t.so_type,
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
NULL,
t.so_quantity),
t.so_quantity),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
NULL,
t.internal_so_quantity),
t.internal_so_quantity),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
NULL,
t.actual_so_quantity),
t.actual_so_quantity),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
NULL,
t.so_revenue),
t.so_revenue),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
NULL,
t.internal_so_revenue),
t.internal_so_revenue),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
NULL,
t.actual_so_revenue),
t.actual_so_revenue),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'64010102',
NULL,
t.so_cost),
t.so_cost),
DECODE('NET',
'TOTAL',
DECODE(SUBSTR(t.segment3, 1, 8),
'64010102',
NULL,
t.internal_so_cost),
t.internal_so_cost),
t.so_cost_diff,
(decode(t.actual_so_revenue,
0,
NULL,
NULL,
NULL,
round(100 *
(nvl(t.so_cost_diff, 0) - nvl(t.expense_amount, 0)) /
t.actual_so_revenue,
2))),
t.expense_amount,
t.margin_amount,
(decode(t.actual_so_revenue,
0,
NULL,
NULL,
NULL,
round(100 *
(nvl(t.so_cost_diff, 0) - nvl(t.expense_amount, 0)) /
t.actual_so_revenue,
2))),
abs(decode(t.actual_so_revenue,
0,
NULL,
NULL,
NULL,
round(100 * t.expense_amount / t.actual_so_revenue, 2))),
t.so_number,
t.so_line_num,
t.ar_trx_number,
t.ar_trx_line_num,
t.gl_je_name,
t.gl_je_line_num,
t.lot_number,
t.inv_organization_name,
t.inv_item_number,
t.inv_item_description,
t.plan_po_number,
t.plan_po_line_number,
t.po_number,
t.po_line_number,
t.ap_invoice_number,
t.ap_invoice_line_num,
t.ra_trx_type_name,
t.so_party_name,
t.po_vendor_name,
t.so_name,
t.po_name,
to_char(t.trans_date, 'YYYY-MM-DD HH24:MI:SS'),
t.po_type1,
t.comments,
t.sales_type,
t.primary_uom_code,
t.project_number_desc,
t.sales_percentage_rate,
t.summary,
t.so_country_name,
t.rec_method,
t.blanket_number,
t.source_type,
nvl(t.so_cost, 0) - nvl(t.purchase_cost, 0) -
nvl(t.sales_cost, 0),
t.purchase_cost,
t.sales_cost,
t.innerordercode,
t.parent_project_number,
nar_ar14_analysis_extract_pkg.get_out_contract_number(t.plan_po_number,
t.project_number,
t.org_id)
,DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
DECODE((SELECT COUNT(*)
FROM gl_je_headers gjh,
gl_je_sources_tl gs
WHERE gjh.je_header_id = t.je_header_id
AND gjh.je_source = gs.je_source_name
AND gs.language = 'ZHS'
AND gs.user_je_source_name IN
('人工', '自动复制')),
0,
NULL,
(SELECT TO_NUMBER(gjl.attribute5) *
DECODE(nvl(nvl(gjl.accounted_dr,
gjl.entered_dr),
0),
0,
-1,
1)
FROM gl_je_lines gjl
WHERE gjl.je_header_id = t.je_header_id
AND gjl.je_line_num = t.gl_je_line_num)),
NULL),
DECODE(SUBSTR(t.segment3, 1, 8),
'60010118',
DECODE((SELECT COUNT(*)
FROM gl_je_headers gjh,
gl_je_sources_tl gs
WHERE gjh.je_header_id = t.je_header_id
AND gjh.je_source = gs.je_source_name
AND gs.language = 'ZHS'
AND gs.user_je_source_name IN
('人工', '自动复制')
),
0,
NULL,
(SELECT nvl(gjl.accounted_cr, 0) -
nvl(gjl.accounted_dr, 0)
FROM gl_je_lines gjl
WHERE gjl.je_header_id = t.je_header_id
AND gjl.je_line_num = t.gl_je_line_num)),
NULL),
DECODE(SUBSTR(t.segment3, 1, 8),
'64010102',
DECODE((SELECT COUNT(*)
FROM gl_je_headers gjh,
gl_je_sources_tl gs
WHERE gjh.je_header_id = t.je_header_id
AND gjh.je_source = gs.je_source_name
AND gs.language = 'ZHS'
AND gs.user_je_source_name IN
('人工', '自动复制')),
0,
NULL,
(SELECT nvl(gjl.accounted_dr, 0) -
nvl(gjl.accounted_cr, 0)
FROM gl_je_lines gjl
WHERE gjl.je_header_id = t.je_header_id
AND gjl.je_line_num = t.gl_je_line_num)),
NULL), 'RST' FROM x t ---x原本是一个超大的SELECT语句，它没有性能瓶颈，为了简化SQL，创建临时表x代替
);x一共有4768314行数据，没有过滤条件
SQL> select count(*) from x;
COUNT(*)
----------
4768314
SQL里面有一堆标量子查询和自定义函数，肯定是标量子查询或者自定义函数影响了SQL的性能
可以把SQL拆了，注释掉自定义函数或者注释掉标量子查询，再跑SQL看谁影响了SQL性能
最终定位到是自定义函数拖慢了整个SQL
nar_ar14_analysis_extract_pkg.get_out_contract_number(t.plan_po_number,
t.project_number,
t.org_id)
自定义函数的代码如下：
FUNCTION get_out_contract_number(p_plan_po_number IN VARCHAR2
,p_project_number IN VARCHAR2
,p_org_id IN NUMBER) RETURN VARCHAR2 IS
l_return VARCHAR2(240);
BEGIN
IF p_plan_po_number IS NOT NULL THEN
SELECT pha.attribute1
INTO l_return
FROM po_headers_all pha
WHERE pha.type_lookup_code = 'PLANNED'
AND pha.attribute_category = 'CONTRACT'
AND pha.segment1 = p_plan_po_number
AND pha.org_id = p_org_id
AND pha.attribute1 IS NOT NULL
AND ROWNUM = 1;
ELSIF p_project_number IS NOT NULL THEN
SELECT pha.attribute1
INTO l_return
FROM po_distributions_all pda
,po_headers_all pha
,pa_projects_all ppa
WHERE pha.po_header_id = pda.po_header_id
AND pda.project_id = ppa.project_id
AND pha.type_lookup_code = 'PLANNED'
AND pha.attribute_category = 'CONTRACT'
AND ppa.segment1 = p_project_number
AND rownum = 1;
ELSE
l_return := NULL;
END IF;
RETURN l_return;
EXCEPTION
WHEN OTHERS THEN
RETURN NULL;
END get_out_contract_number;通过监控ASH，也能定位到是自定义函数拖慢了整个SQL
SQL> select sql_id, sql_child_number, event, top_level_sql_id, count(*)
2 from gv$active_session_history
3 where session_id = 937
4 and sample_time >
5 to_date('2022-12-01 14:18:00', 'yyyy-mm-dd hh24:mi:ss')
6 group by sql_id, sql_child_number, event, top_level_sql_id
7 order by 5 desc;
SQL_ID SQL_CHILD_NUMBER EVENT TOP_LEVEL_SQL_ID COUNT(*)
------------- ---------------- ------------------------------- ---------------- ----------
16j3dr5ws843j 5 1upgmu861mtaz 3110
1upgmu861mtaz 0 1upgmu861mtaz 55
-1 1upgmu861mtaz 3
1upgmu861mtaz 0 db file sequential read 1upgmu861mtaz 2
0 1
264xbz7w614gx 5 1upgmu861mtaz 1
SQL> select sql_text from v$sql where sql_id='16j3dr5ws843j' and rownum=1;
SQL_TEXT
--------------------------------------------------------------------------------
SELECT PHA.ATTRIBUTE1 FROM PO_DISTRIBUTIONS_ALL PDA ,PO_HEADERS_ALL PHA ,PA_PROJ
SQL> select sql_text from v$sql where sql_id='1upgmu861mtaz' and rownum=1;
SQL_TEXT
--------------------------------------------------------------------------------
INSERT INTO nso_allocaton_fr_tmp (create_date, request_id, c1, c2,定位到是因为自定义函数部分拖慢了性能就好办了
优化方法一：
将自定义函数的逻辑改写为标量子查询(为了方便读者阅读，进一步简化了SQL，省略了其他列)
SQL> INSERT INTO nso_allocaton_fr_tmp
2 (c65)
3 (SELECT
4 case
5 when plan_po_number IS NOT NULL THEN
6 (SELECT pha.attribute1
7 FROM po_headers_all pha
8 WHERE pha.type_lookup_code = 'PLANNED'
9 AND pha.attribute_category = 'CONTRACT'
10 AND pha.segment1 = t.plan_po_number
11 AND pha.org_id = t.org_id
12 AND pha.attribute1 IS NOT NULL
13 AND ROWNUM=1
14 )
15 when project_number IS NOT NULL THEN
16 (SELECT pha.attribute1
17 FROM po_distributions_all pda,
18 po_headers_all pha,
19 pa_projects_all ppa
20 WHERE pha.po_header_id = pda.po_header_id
21 AND pda.project_id = ppa.project_id
22 AND pha.type_lookup_code = 'PLANNED'
23 AND pha.attribute_category = 'CONTRACT'
24 AND ppa.segment1 = t.project_number
25 AND ROWNUM=1
26 )
27 else null end FROM x t
28 );
4768314 rows inserted
Executed in 21.315 seconds优化方法二：
不改写自定义函数逻辑，把对自定义函数的直接访问改成标量子查询+dual来访问
SQL> INSERT INTO nso_allocaton_fr_tmp
2 (c65)
3 (SELECT (select nar_ar14_analysis_extract_pkg.get_out_contract_number(t.plan_po_number,
4 t.project_number,
5 t.org_id)
6 from dual)
7 FROM x t);
4768314 rows inserted
Executed in 25.836 seconds优化方法一跑了21秒，优化方法二跑了25秒，优化方法二多出来的4秒是SQL引擎和PLSQL引擎上下文切换引起的
读者可能会有疑问，为什么将SQL
INSERT INTO nso_allocaton_fr_tmp
(c65)
(SELECT nar_ar14_analysis_extract_pkg.get_out_contract_number(t.plan_po_number,
t.project_number,
t.org_id)
FROM x t);
改成
INSERT INTO nso_allocaton_fr_tmp
(c65)
(SELECT (select nar_ar14_analysis_extract_pkg.get_out_contract_number(t.plan_po_number,
t.project_number,
t.org_id)
from dual)
FROM x t);
就能从2个多小时优化到几十秒呢？
那是因为没有改写之前，函数nar_ar14_analysis_extract_pkg.get_out_contract_number要被调用4768314次
而改写之后，函数nar_ar14_analysis_extract_pkg.get_out_contract_number只会被调用2485次(标量子查询特性)
SQL> select count(*)
2 from (
3 select t.plan_po_number, t.project_number, t.org_id
4 from x t
5 group by t.plan_po_number, t.project_number, t.org_id);
COUNT(*)
----------
2485
如果函数传参的列是主键，那么前面两种优化方法都不对，需要将函数的SQL改写为LEFT JOIN，这里就不做展示了
各位读者，如果以后遇到了自定义函数引起SQL慢，自定义函数是直接访问(没有通过select...dual访问)
自定义函数逻辑非常复杂(改写困难)，传参列distinct值少，可以采用本案例第二种优化方法试一试
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