SQL查询获取两张表中一列唯一值的所有记录

Question

I am using SQL Server 2012 and Access.

I have two tables indexed on Well and Depth. The depths in each table for each well can be the same or different. I wish to create a single table with Well, Depth (one column each) and all other columns of the two tables, containing a list of all unique depths and the associated data at each depth.

The tables shown here are an example:

Table PT

Well	Depth	Temperature
A1	100	10
A1	150	15
A1	200	20
A1	250	25
A1	300	30
A2	69	121

Table SPIN

Well	Depth	Frequency
A1	100	1000
A1	120	1200
A1	200	2000
A1	300	3000
A1	500	5000
B2	103	250

The combined table, SPINPT, for well A1 should look like this:

Well	Depth	Temperature	Frequency
A1	100	10	1000
A1	120		1200
A1	150	15
A1	200	20	2000
A1	250	25
A1	300	30	3000
A1	500		5000

I hoped this would be fairly easy, but I have searched the internet for solutions without success.

Answer 1

You seem to want a full outer join between the two tables:

SELECT
    COALESCE(p.Well, s.Well) AS Well,
    COALESCE(p.Depth, s.Depth) AS Depth,
    p.Temperature,
    s.Frequency
FROM PT p
FULL OUTER JOIN SPIN s
    ON s.Well = p.Well AND
       s.Depth = p.Depth
ORDER BY
    Well,
    Depth;

Demo