January 21, 2016 at 7:55 am
I need to pull data from 3 tables where one of the columns is a reference column and is used twice in the return data. So I have table three tables
Student s
id name age
Grades g
studentid class grade
Codes c
studentid cde_variable cde_value
I need SELECT s.id, c.cde.value AS 'teacher' where c.cde_varlable = 'a', c.cde_value AS 'school' where c.cde_variable = 'b' and where s.id= g.studentid AND g.studentid = c.studentid.
The reference column is cde_value, so I need to search it using two different filters in the same query. So I thought about using a union.
StudentID Teacher School
123 Jones ' '
345 Thomas ' '
UNION
StudentID Teacher School
123 ' ' Memorial High
345 ' ' Science Academy
But I get (Below are column but I couldn't draw a table)
StudentID Teacher School
123 Jones ' '
345 Thomas ' '
123 ' ' Memorial High
345 ' ' Science Academy
How can I get this query together?
January 21, 2016 at 8:02 am
Hi......if you could provide some scripts that give table structure / sample data / expected results (based on sample data)...then that will help us all.
http://spaghettidba.com/2015/04/24/how-to-post-a-t-sql-question-on-a-public-forum/
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you can lead a user to data....but you cannot make them think
and remember....every day is a school day
January 21, 2016 at 8:30 am
You just need to use 2 joins in your query.
There's an example at the bottom of this page: http://www.sql-join.com/
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