问题
I have below query. the below query has union all twice. Due to this ,query is waiting for the same resource and wait time is too high. Below is the output of sql trace.
Elapsed times include waiting on following events:
Event waited on Times Max. Wait Total Waited
---------------------------------------- Waited ---------- ------------
SQL*Net message to client 1 0.00 0.00
Disk file operations I/O 1047 0.00 0.15
db file sequential read 167048 0.64 1584.33
db file parallel read 216 0.05 1.37
read by other session 520944 0.71 5113.10
latch: cache buffers chains 31768 0.00 1.32
db file scattered read 50 0.01 0.14
wait list latch free 1 0.00 0.00
you can see read by other session parameter. is there anyway to make below query so that this time can be reduced?
SELECT
mmt . transaction_date Txn_date ,
GCC.SEGMENT1||'
'||GCC.SEGMENT2||'
'||GCC.SEGMENT3||'
'||GCC.SEGMENT4||'
'||GCC.SEGMENT5||'
'||GCC.SEGMENT6 C_acct_flex1 ,
MSI.SEGMENT1 C_item_flex1 ,
msi . description Description ,
mtt.transaction_type_name Type ,
mmt . transaction_source_type_id Type_id ,
mmt . organization_id Org_id ,
DECODE ( mmt . transaction_source_type_id ,
1 , to_char ( mmt . transaction_source_id ) ,
2 , MKTS.SEGMENT1||''||MKTS.SEGMENT2||''||MKTS.SEGMENT3 ,
3 , GL.SEGMENT1||''||GL.SEGMENT2||''||GL.SEGMENT3||''||GL.SEGMENT4||''||GL.SEGMENT5||''||GL.SEGMENT6 ,
5 , to_char ( mmt . transaction_source_id ) ,
6 , MDSP.SEGMENT1 ,
7 , to_char ( mmt . transaction_source_id ) ,
8 , MKTS.SEGMENT1||''||MKTS.SEGMENT2||''||MKTS.SEGMENT3 ,
9 , to_char ( mmt . transaction_source_id ) ,
10 , to_char ( mmt . transaction_source_id ) ,
11 , to_char ( mmt . transaction_source_id ) ,
12 , MKTS.SEGMENT1||''||MKTS.SEGMENT2||''||MKTS.SEGMENT3 , mmt . transaction_source_name )
Source ,
decode ( cal . accounted_dr ,
NULL , - 1 * ABS ( mmt . primary_quantity ) , ABS ( mmt . primary_quantity ) ) Quantity ,
msi . primary_uom_code Primary_uom ,
round ( cal . rate_or_amount * : P_EXCHANGE_RATE , : cp_ext_precision ) Cost ,
nvl ( nvl ( cal . accounted_dr , - 1 * cal . accounted_cr ) , 0 ) * : P_EXCHANGE_RATE Value ,
cal . ae_line_id
FROM
cst_ae_headers cah ,
mtl_material_transactions mmt ,
mtl_item_categories mic ,
mtl_system_items msi ,
MTL_SALES_ORDERS mkts ,
MTL_GENERIC_DISPOSITIONS mdsp ,
gl_code_combinations gl ,
mtl_transaction_types mtt ,
cst_ae_lines cal ,
gl_code_combinations gcc
WHERE
cah . ae_header_id = cal . ae_header_id AND
cah . accounting_event_id = mmt . transaction_id AND
cah . acct_event_source_table = 'MMT' AND
cal . code_combination_id = gcc . code_combination_id AND
mmt . inventory_item_id = msi . inventory_item_id AND
mmt . organization_id = msi . organization_id AND
mmt . organization_id = nvl ( mmt . owning_organization_id , mmt . organization_id ) AND
nvl ( mmt . owning_tp_type , 2 ) = 2 AND
cah . cost_group_id = : P_cost_group_id AND
cah . cost_type_id = : P_cost_type_id AND
cah . period_id = : P_period_id AND
GCC.SEGMENT1 = '0731' AND
GCC.SEGMENT2 BETWEEN '75000' AND '95999' AND
GCC.SEGMENT3 BETWEEN '00000' AND '99999' AND
GCC.SEGMENT4 BETWEEN '00000' AND '99999' AND
GCC.SEGMENT5 = '0000' AND
GCC.SEGMENT6 = '00000' AND 1 = 1 AND 1 = 1 AND
mmt.transaction_type_id = mtt.transaction_type_id AND
mmt.inventory_item_id = mic.inventory_item_id AND
mmt.organization_id = mic.organization_id AND
mic.category_set_id = 1 AND
( mmt . transaction_source_type_id = : P_source_type_id OR : P_source_type_id IS NULL ) AND
( mmt . transaction_type_id = : P_txn_type_id OR : P_txn_type_id IS NULL ) AND
mmt . transaction_source_id = mkts . sales_order_id (+) AND
mmt . transaction_source_id = mdsp . disposition_id (+) AND
mmt . transaction_source_id = gl . code_combination_id (+)
UNION ALL
SELECT
rt . transaction_date Txn_date ,
GCC.SEGMENT1||'
'||GCC.SEGMENT2||'
'||GCC.SEGMENT3||'
'||GCC.SEGMENT4||'
'||GCC.SEGMENT5||'
'||GCC.SEGMENT6 C_acct_flex1 ,
MSI.SEGMENT1 C_item_flex1 ,
msi . description Description ,
rt.transaction_type Type ,
0 Type_id ,
0 Org_id ,
null Source ,
decode ( rt . po_distribution_id ,
NULL , decode ( cal . accounted_dr , NULL , - 1 * ABS ( rt . primary_quantity ) ,
ABS ( rt . primary_quantity ) ) * POD . QUANTITY_ORDERED / POLL . QUANTITY , decode ( cal . accounted_dr , NULL , - 1 * ABS ( rt . primary_quantity ) , ABS ( rt . primary_quantity ) ) ) Quantity , msi . primary_uom_code Primary_uom , round ( cal . rate_or_amount * : P_EXCHANGE_RATE , : cp_ext_precision ) Cost , nvl ( nvl ( cal . accounted_dr , - 1 * cal . accounted_cr ) , 0 ) * : P_EXCHANGE_RATE Value , cal . ae_line_id
FROM
cst_ae_headers cah ,
cst_ae_lines cal ,
mtl_system_items_vl msi ,
rcv_transactions rt ,
rcv_shipment_lines rsl ,
gl_code_combinations gcc ,
po_distributions_all pod ,
po_line_locations_all poll ,
mtl_item_categories mic
WHERE
pod . line_location_id = poll . line_location_id and
poll . line_location_id = rt . po_line_location_id and
pod . po_distribution_id = nvl ( rt . po_distribution_id , pod . po_distribution_id ) and
pod . po_distribution_id = cal . po_distribution_id and
cah . ae_header_id = cal . ae_header_id AND
cah . accounting_event_id = rt . transaction_id AND
cah . acct_event_source_table = 'RT' AND
cal . code_combination_id = gcc . code_combination_id AND
rt . shipment_line_id = rsl . shipment_line_id AND
NVL ( rt . consigned_flag , 'N' ) = 'N' AND
rsl . item_id = msi . inventory_item_id (+) AND
cah . organization_id = msi . organization_id AND
cah . cost_group_id = : P_cost_group_id AND
cah . cost_type_id = : P_cost_type_id AND
cah . period_id = : P_period_id AND
GCC.SEGMENT1 = '0731' AND
GCC.SEGMENT2 BETWEEN '75000' AND '95999' AND
GCC.SEGMENT3 BETWEEN '00000' AND '99999' AND
GCC.SEGMENT4 BETWEEN '00000' AND '99999' AND
GCC.SEGMENT5 = '0000' AND
GCC.SEGMENT6 = '00000' AND 1 = 1 AND 1 = 1 AND
rsl.item_id = mic.inventory_item_id
AND cah.organization_id = mic.organization_id
AND mic.category_set_id = 1 and 1 = 1
UNION ALL
SELECT rae . transaction_date Txn_date , GCC.SEGMENT1||'
'||GCC.SEGMENT2||'
'||GCC.SEGMENT3||'
'||GCC.SEGMENT4||'
'||GCC.SEGMENT5||'
'||GCC.SEGMENT6 C_acct_flex1 ,
MSI.SEGMENT1 C_item_flex1 ,
msi . description Description ,
decode ( : P_type_option ,
1 , rt . source_document_code , decode ( rae . event_type_id , 18 , raet . description , 19 , raet . description , 20 , raet . description , raet . event_type_name ) ) Type ,
0 Type_id , 0 Org_id , null Source , decode ( cal . accounted_dr , NULL , - 1 * ABS ( rae . primary_quantity ) , ABS ( rae . primary_quantity ) ) Quantity ,
msi . primary_uom_code Primary_uom ,
round ( cal . rate_or_amount * : P_EXCHANGE_RATE , : cp_ext_precision ) Cost ,
nvl ( nvl ( cal . accounted_dr , - 1 * cal . accounted_cr ) , 0 ) * : P_EXCHANGE_RATE Value ,
cal . ae_line_id
FROM
cst_ae_headers cah ,
cst_ae_lines cal ,
mtl_system_items msi ,
rcv_transactions rt ,
rcv_accounting_events rae ,
rcv_shipment_lines rsl ,
gl_code_combinations gcc ,
rcv_Accounting_event_types raet ,
mtl_item_categories mic
WHERE
cah . ae_header_id = cal . ae_header_id AND
cah . accounting_event_id = rae . accounting_event_id and
rae . rcv_transaction_id = rt . transaction_id AND
cah . acct_event_source_table = 'RAE' AND
cal . code_combination_id = gcc . code_combination_id AND
rt . shipment_line_id = rsl . shipment_line_id AND
NVL ( rt . consigned_flag , 'N' ) = 'N' AND
rsl . item_id = msi . inventory_item_id (+) AND
cah . organization_id = msi . organization_id AND
cah . cost_group_id = : P_cost_group_id AND
cah . cost_type_id = : P_cost_type_id AND
cah . period_id = : P_period_id AND
raet . event_type_id = rae . event_type_id AND
GCC.SEGMENT1 = '0731' AND
GCC.SEGMENT2 BETWEEN '75000' AND '95999'
AND GCC.SEGMENT3 BETWEEN '00000' AND '99999'
AND GCC.SEGMENT4 BETWEEN '00000' AND '99999'
AND GCC.SEGMENT5 = '0000'
AND GCC.SEGMENT6 = '00000' AND 1 = 1 AND 1 = 1
AND rsl.item_id = mic.inventory_item_id
AND cah.organization_id = mic.organization_id
AND mic.category_set_id = 1
ORDER BY 2 asc , 1 asc , 3 asc , 5 asc , 7 asc , 8 asc , 9 asc , 11 asc
Is there anyway to optimize the above query? even your small suggestion would be highly helpful
来源：https://stackoverflow.com/questions/57020943/query-very-slow-the-issue-is-read-by-other-session-due-to-union-all