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SQL join when tables are separated by one or more other tables

Say in an SQL database I have an "Employee" table, which points to a "Person" table, which points to a Person_Name table:

Employee (table)
+------------+-----+      Person (table)
| Field      | Key |      +------------+-----+      Person_Name (table)
+------------+-----+      | Field      | Key |      +------------+-----+
| employee_id| PK  |      +------------+-----+      | Field      | Key |
| person_id  | FK  | -->  | person_id  | PK  |      +------------+-----+
+------------+-----+      | name_id    | FK  | -->  | name_id    | PK  |
                          +------------+-----+      | people_id  | FK  |
                                                    | name       |     |
                                                    +------------+-----+

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What query would list me all employees and their names?

ASKER CERTIFIED SOLUTION

Jim Horn

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deleyd

ASKER

Thank you for the query. I seem to get no result from it. I created a test database and filled it in as follows:

Employee (table)              Person (table)               Person_Name (table)
+------------+---------+      +------------+--------+      +----------+------+
| employee_id|person_id|      | person_id  | name_id|      | name_id  | name |
+------------+---------+      +------------+--------+      +----------+------+
|     1      |   10    |      |    10      |  100   |      |   100    | One  |
|     2      |   20    | -->  |    20      |  200   | -->  |   200    | Two  |
|     3      |   30    |      |    30      |  300   |      |   300    | Three|
+------------+---------+      +------------+--------+      +----------+------+

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Then run the query, which doesn't complain, but also gives me no results. Hmm..,
٩(͡๏̯͡๏)۶
(I also removed the people_id from the Person_Name table which served no purpose.)

SOLUTION

Vitor Montalvão

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deleyd

ASKER

Thank you for your help. I'm stumped on this one, why I'm getting no results, so I made some screen shots and attached them here. Hopefully someone can spot the problem.
Person Database

Name Database

Employee Database

Query2 Results

Query1 Results

deleyd

ASKER

Oh I see the problem.

deleyd

ASKER

OK Thank you I'll use the Image button next time.

Both queries work now.

So I see one pattern is:
SELECT
FROM
JOIN
JOIN
ON
ON

and the other pattern is:
SELECT
FROM
JOIN ... ON ...
JOIN ... ON ...

I suppose both work fine. Thank you for your help!

Vitor Montalvão

So, name_id wasn't equal :)
Machine is always right ;)

deleyd

ASKER

(I have a T-shirt with a human working at the computer. Human thinks, "Stupid computer." Computer thinks, "Stupid human.")

:)