Hi Gurus,
I have a table with 73 columns in it, with data_type count as below
data_type | count
------------------+-------
Date | 3
NCLOB | 12
INTEGER | 25
NVARCHAR2(255) | 20
NUMBER | 13
In the application, code had multiple update statements (something like 14
update
statement) with few columns
I recommended to consolidate all the multiple update statements into a
single
large update statement, and commit once
Now, with this change, performance team is reporting regressions for all
the
operations that are happening on the table.
Question:
1) Is this bad solution (more curious to know why sql execution is taking
longer)?
2) Is there a way to measure why sql execution is taking longer?
e.g:
== BEFORE ==
UPDATE T1 set c2 = $1, c3=$2 WHERE c1=$3;
UPDATE T1 set c5 = $1, c7=$2, c8=$3, c11=$4 WHERE c1=$5;
UPDATE T1 set c22 = $1, c32=$2 WHERE c1=$3;
UPDATE T1 SET C10 = $1 , C12 = $2 , C21 = $3 , C31 = $4 , C41 = $5 , C43 =
$6 ,
C44 = $7 , C45 = $8 , C46 = $9 , C47 = $10 , C48 = $11 , C49 = $12 WHERE C1
= $13
== AFTER ==
UPDATE T1 set c2 = $1, c3=$2, c5 = $3, c7=$4, c8=$5, c11=$6, c22 = $7,
c32=$8,
C10 = $9 , C12 = $10 , C21 = $11 , C31 = $12 , C41 = $13 , C43 = $14 ,
C44 = $15 , C45 = $16 , C46 = $17 , C47 = $18 , C48 = $19 , C49 = $20
WHERE C1 = $21;
Could you please provide some light, so I can investigate and explain it to
my
perf team for why this is happening?
--
Thank you
NikTeki
