# performance tuning on simple update query

**URL:** <https://forums.percona.com/t/performance-tuning-on-simple-update-query/1135>\
**Category:** Other MySQL® Questions\
**Created:** [April 2, 2009, 2:40am UTC](https://forums.percona.com/t/performance-tuning-on-simple-update-query/1135 "2009-04-02T02:40:59Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![rajesh.vijayan](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@rajesh.vijayan](https://forums.percona.com/u/rajesh.vijayan)\
**Post date:** [April 2, 2009, 2:40am UTC](https://forums.percona.com/t/performance-tuning-on-simple-update-query/1135/1 "2009-04-02T02:40:59Z")

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hi,

here is the simple update query which takes more than 20sec :roll:

UPDATE audience\_member\_reg SET completed\_page\_no = 2, reg\_datetime = ‘2009-03-28 07:13:45’ WHERE audience\_member\_reg\_id = 6640737;

explain statements are,

mysql\> explain select completed\_page\_no,reg\_datetime from audience\_member\_reg where audience\_member\_reg\_id = 6640737\G  
\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* 1. row \*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*  
id: 1  
select\_type: SIMPLE  
table: NULL  
type: NULL  
possible\_keys: NULL  
key: NULL  
key\_len: NULL  
ref: NULL  
rows: NULL  
Extra: Impossible WHERE noticed after reading const tables  
1 row in set (0.00 sec)

is there anyway this query can be improved upon? could anyone please help me out. thanks for your response.

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<div class="post-metadata">

**Author:** ![januzi](https://avatars.discourse-cdn.com/v4/letter/j/82dd89/32.png) [@januzi](https://forums.percona.com/u/januzi)\
**Post date:** [April 2, 2009, 8:05am UTC](https://forums.percona.com/t/performance-tuning-on-simple-update-query/1135/2 "2009-04-02T08:05:23Z")

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Use explain with valid audience\_member\_reg\_id.

What is the type of the table: myisam or innodb ?  
How many rows are there ?

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<div class="post-metadata">

**Author:** ![rajesh.vijayan](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@rajesh.vijayan](https://forums.percona.com/u/rajesh.vijayan)\
**Post date:** [April 2, 2009, 8:54am UTC](https://forums.percona.com/t/performance-tuning-on-simple-update-query/1135/3 "2009-04-02T08:54:48Z")

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hi,  
Thanks for you reply.

this is Innodb engine. this table has nearly 5 millon of records.

and audience\_member\_reg\_id is the primary key.