tagged [group-by]
Is there any difference between GROUP BY and DISTINCT
Is there any difference between GROUP BY and DISTINCT I learned something simple about SQL the other day: Has the same result as: What I am curious of, is there anything different in the way an SQL en...
mysql count group by having
mysql count group by having I have this table: A movie can have multiple genres, so an ID is not specific to a genre, it is a many to many relationship. I want a query to find the total number of movi...
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- 22 Oct at 05:18
Group by month and year in MySQL
Group by month and year in MySQL Given a table with a timestamp on each row, how would you format the query to fit into this specific json object format. I am trying to organize a json object into yea...
Linq GroupBy with each null value as a group
Linq GroupBy with each null value as a group I have an object with a nullable int property "GroupId". With a List of this object, I would like to do a GroupBy on this "GroupId". But if I do it, all th...
Entity Framework skip take by group by
Entity Framework skip take by group by I a currently "paging" through a table ("Table1") that has the following fields { Policy, Name, Amount, Date} and there can be mulitple records in "Table1" for a...
Relative frequencies / proportions with dplyr
Relative frequencies / proportions with dplyr Suppose I want to calculate the proportion of different values within each group. For example, using the `mtcars` data, how do I calculate the frequency o...
How to concatenate strings of a string field in a PostgreSQL 'group by' query?
How to concatenate strings of a string field in a PostgreSQL 'group by' query? I am looking for a way to concatenate the strings of a field within a group by query. So for example, I have a table: | I...
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- 28 Feb at 09:42
Linq Grouping - aggregate, outside of a group by
Linq Grouping - aggregate, outside of a group by I've got a SQL query, that works as follows: How can I write an identical Linq query? The issue is, that as soon as I apply my grouping, I cannot acces...
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- 22 Apr at 13:58
Group by variable integer range using Linq
Group by variable integer range using Linq I'm trying to group a set of data based on the range of an integer, by the range does not increase at a fixed interval. e.g. I have Item ID Price 1 ...
C# Linq Group By on multiple columns
C# Linq Group By on multiple columns ``` public class ConsolidatedChild { public string School { get; set; } public string Friend { get; set; } public string FavoriteColor { get; set; } public...
sql group by versus distinct
sql group by versus distinct Why would someone use a group by versus distinct when there are no aggregations done in the query? Also, does someone know the group by versus distinct performance conside...
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- 12 Feb at 04:28
Group by range using linq
Group by range using linq how can we use groupped ranges for equal or greater than ? ``` var data = new[] { new { Id = 0, Price = 2 }, new { Id = 1, Price = 10 }, new { Id = 2, Price = 30 }, ...
LINQ to SQL: GroupBy() and Max() to get the object with latest date
LINQ to SQL: GroupBy() and Max() to get the object with latest date Consider a SQL Server table that's used to store events for auditing. The need is to get only that for each CustID. We want to get t...
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- 10 Nov at 00:9
group by week in pandas
group by week in pandas I'm having this data frame: I want to aggregate this by `Name` and `Date` to get sum of quantities Details: : Group, the result should be at the beginning of the week (or just ...
How to select the first row for each group in MySQL?
How to select the first row for each group in MySQL? In C# it would be like this: Linq-To-Sql translates it to the following T-SQL code: ``` SELECT [t3].[AnotherColumn], [t3].[SomeColumn] FROM ( SEL...
LINQ Group By and select collection
LINQ Group By and select collection I have this structure I want to generate a list of `CustomerItems` via LINQ given a subset of `OrderItems`: which is a grouping of all the items a Customer has orde...
Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
Get statistics for each group (such as count, mean, etc) using pandas GroupBy? I have a data frame `df` and I use several columns from it to `groupby`: In the above way I almost get the table (data fr...
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- 28 Jun at 02:56
Client side GroupBy is not supported
Client side GroupBy is not supported I have the following Entity Framework Core 3.0 query: I get the following error: To run the query on the client, or par
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- 20 Mar at 18:12
linq distinct or group by multiple properties
linq distinct or group by multiple properties How can I using c# and Linq to get a `result` from the next list: ``` var pr = new List() { new Product() {Title="Boots",Color="Red", Price=1}, ne...
ORDER BY date and time BEFORE GROUP BY name in mysql
ORDER BY date and time BEFORE GROUP BY name in mysql i have a table like this: i want oldest name first: (->doesn't work!) now it should give me first mad(has earlier date) then tom
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- 2 Feb at 13:49
Group dataframe and get sum AND count?
Group dataframe and get sum AND count? I have a dataframe that looks like this: ``` Company Name Organisation Name Amount 10118 Vifor Pharma UK Ltd Welsh Assoc for Gastro & Endo 2700.00 10119 Vi...
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- 20 Dec at 07:41
LINQ: combining join and group by
LINQ: combining join and group by I have a query that combines a join and a group, but I have a problem. The query is like: ``` var result = from p in Products join bp in BaseProducts on ...
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- 30 Sep at 12:43