Optimize a MySQL query to find duplicate records

$30-250 USD

Lezárt

Kiadva ekkor:

több mint 6 évvel ezelőtt

$30-250 USD

Teljesítéskor fizetve

We are porting some code from MS-SQL to MySQL and are looking for help optimizing a query or procedure to find duplicate records. The table is properly indexed and is about 6GB with 40+ columns and 20+ million rows. It needs to compare 8 columns. We want to keep the row with the lowest Id for each set of duplicates. This is an advanced problem and not solved by a simple GROUP BY / HAVING clause. On SQL Server the query takes <18 seconds. On MySQL, a fairly simple version of our query takes 30+ minutes and the best we have been able to do with some tricks is 5 minutes. We would like to have MySQL perform approximately as well as MS-SQL. We are fairly skilled at SQL so please only bid if you have *advanced expertise* with MySQL query optimization.

Database Administration

Database Programming

MySQL

SQL

Projektazonosító: 15540253

A projektről

20 ajánlat

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Aktiválva: 6 évvel ezelőtt

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@softcarve

Hi, I have good experience in sql. I would like to optimize your query snippet. please get in touch to discuss more. Relevant Skills and Experience mysql, ms sql Proposed Milestones $55 USD - milestone

$55 USD 3 napon belül

4,9

(95 értékelés)

5,9

@stivens

Hello, are you able to provide the query you are trying to optimize? Also what is the storage engine? MyISAM? InnoDB? or other? Please message me to discuss more details. Thank you Stay tuned, I'm still working on this proposal.

$80 USD 3 napon belül

5,0

(21 értékelés)

5,1

@RajakScripts

That's a one challenging task! Could you inform the exported table structures here in gzipped so I can import it into my local DB, to imagine & figure it out the best way to find duplicate records? Relevant Skills and Experience I've been using MySQL since 2004. Proposed Milestones $55 USD - Provide the MySQL query to find duplicate records If it's possible, please also attach some records (1000's records only, do not more!), thanks!

$55 USD 2 napon belül

5,0

(30 értékelés)

5,3

@danale72

Hi This might be challenging and this is exactly why I am interested in this task. Relevant Skills and Experience MySql, indexing, optimization Proposed Milestones $100 USD - Final acceptance I would like to see -SHOW CREATE TABLE <table we are talking about> -GROUP BY of the query Thanks

$100 USD 5 napon belül

4,9

(56 értékelés)

5,4

@vinaysinghh

I am mysql dba having more then 10 yrs of experience

$55 USD 1 napon belül

4,6

(65 értékelés)

5,4

@scsBiswas

I can do it

$100 USD 2 napon belül

5,0

(33 értékelés)

4,8

@rameshweb212

I will make perfect query to find duplicate records from 6GB database. Relevant Skills and Experience I have 12 years of professional experience and love to work on challenging task surrender by top freelancers. I am hardworking, confident so promise to deliver 100% working solution. Proposed Milestones $100 USD - query completed

$100 USD 3 napon belül

4,9

(7 értékelés)

3,0

@olevea21

Hello,Hope you doing well.I read your project description,Lets have a technical discussion,negotiate costing, timeline and then we proceed further. I Will show my past work also. Thanks! Relevant Skills and Experience php, wordpress, mysql Proposed Milestones $100 USD - milestone

$100 USD 2 napon belül

0,0

(1 értékelés)

0,0

@billytjan

Saya yakin bisa untuk menyelesaikannya Relevant Skills and Experience Sql managemen

$177 USD 3 napon belül

0,0

(0 értékelés)

0,0

@bwheeler96

I'd like to try looking at the results of the query analyzer and then testing a few tricks I have. The MySQL query optimizer can make illogical decisions, and sometimes requires an explicit "nudge". Relevant Skills and Experience Having worked with MySQL tables of similar size (~16M rows, advertising tech) I'm familiar with this struggle. I've spent 2+ years working with MySQL alone, and about 5 with postgres. Proposed Milestones $155 USD - One and done

$155 USD 3 napon belül

0,0

(0 értékelés)

0,0

@sherryETL

Hey there, luckily I have hands on experience in both sql server and mysql. And I have over seven years experience in database designing and development. Please consider me doing this project for you in an efficient way. If I can have access to the database I will surely device some efficient solution

$111 USD 7 napon belül