Groupwise Max SQL Query Problem
$10-30 USD
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I have a table that has following columns:
coin_id, data_item_id, rating, created_at
For each coin_id there's multiple rows from different data sources (marked with data_item_id), and rating from that data source.. but there are dozens of them. What I need is find the latest row for each data source (data_item_id) and get that row's rating. The output for example coin_id 32 should be:
rating: 69
69 is a SUM of ALL ratings from all "latest (determined by created_at column)" data sources.
If you undestand what I'm trying to say, or you have a concrete question ... bid and contact me, otherwise ..don't bother.
I won't hire somebody that thinks he can solve it (and if you know how it's not difficult) .. but rather somebody that really knows how.
Thanks.
项目ID： #17161183
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有12名威客正在参与此工作的竞标，均价$26/小时
Hi there, I think I can solve it. Let's communicate to proceed further. I am professional and highly motivated, having over 6+ years of DBA and Development work experience in the software industry with MySQL an 更多
Hi, I would like to write the query to get sum of ratings across coin_id and data_item_id from different sources. Available to start now. Get in touch to discuss more. Regards, Manish
hi give me the sampledb i will prepare the query and deliver to you . i could have good experience in writing quieries
Hi, I'm an experienced programmer and Linux systems administrator. Constructing a MySQL as per your request won't be a problem.
Hello How are you I read your job description carefully I have many good experience in Mysql Query I can finish your job quickly and quickly If you hire me, I will do my best and make you satisfied Thanks!
Hello friend, I could help you with the requirement you have. I have the experience in SQL to solve the need you have. Thank you
