grouped

[Amarni]

hi i want to make an select statment that contains some data, that is SELECT Name,ID, Sname,Schools from student imagine that this table have one student have the same ID and same name but i need the last one how can do that while there are no Primary keys . can i use grouped by Name alone or i should make a grouped by name,ID,.. Amarni

[Colin Angus Mackay]

Amarni wrote:

imagine that this table have one student have the same ID and same name but ... there are no Primary keys

So what is ID if not the primary key?

Amarni wrote:

i need the last one

What do you mean by "the last one"? Databases contain sets of data there is no implied order of anything in the database. If you want to make something ordered then it has to be ordered on a column or columns. Which column defines the order?

Amarni wrote:

can i use grouped by Name alone or i should make a grouped by name,ID,..

GROUP BY will allow you to aggregate the other columns based on the column or columns you are GROUPing BY. That means you will no longer be able to access ID, Sname, Schools other than through an aggregation function such as MIN(), MAX(), SUM(), AVG() etc.

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