Mysql Query for Rank (RowNumber) and Groupings -
I have a similar problem
but it is in SQL Server and MySQL "partition support Does not "As I know what can I do now? Here's the question:
I have a table with some columns: User, Category, Value
and I want to do a query which will give me ranking, According to, but reset to the category.
Example:
user1 class A10 user 2 category A11 user 3 category A9 user 4 category B3 user 1 category B11
query must return:
rank user category 1 user 2 category a2 user 1 category 3 user 3 category 1 user 1 category b2 user4 category b
< / Pre>Any ideas?
edit 2 : based on OP's comment:
This works only with some incorrect ranking and it is in the first
rank
. When the toprank
in the samecategories
similarvalue
is one of the first inrank
and the second is in 2bt They have the followingrank
(1)
the following changes have been suggested:
Selection of Rank Please, user, category, price (user select, @cc: = category category, @ cv: = value value, case @ pc = @ cc and @ pv = @ cv, then @rn: = @ rn when @ PC = @cc and @pv! = @vv then @rn: = (@ rn + 1) and ray As a @ rn: = 1 end, @pc: @ccc as temp_currCat, @pv: = @ cv as temp_currVal user_category_values, (select @pc: = '', @cc: = ' ', @pv: =' ', @cv: =' ', @rn: = 0) in order of row_nums category, according to the value) result;
Demo @
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