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mysqlselectcomposite

Select statement across a join table

Have three tables that look like this:

PersonTable
Person.ID
Person.Name

PersonTypeCompositeTable
Person.ID
PersonType.ID

PersonTypeTable
PersonType.ID
PersonType.Category

For this example, say the values of PersonTypeCompositeTable are:

1,A
2,A
3,B

How to I write a SELECT statement that will return all the people with a PersonType of "A"?

UPDATE: (Working version of answer posted)

SELECT p.*
FROM PersonTable p
  INNER JOIN PersonTypeCompositeTable ptc
    ON p.ID = ptc.ID
  INNER JOIN PersonTypeTable pt
    ON ptc.ID = pt.ID
WHERE pt.Category = 'A'
Solution

  • You use joins between the three tables.

    SELECT p.*
FROM PersonTable p
  INNER JOIN PersonTypeCompositeTable ptc
    ON p.Person.ID = ptc.Person.ID
  INNER JOIN PersonTypeTable pt
    ON ptc.PersonType.ID = pt.PersonType.ID
WHERE pt.PersonType.Category = 'A'