where 子句中的 INNER JOIN 表列“ID”不明确

Question

This code created the error.

Error Code: 1052. Column 'ID' in where clause is ambiguous

      SELECT h1.name, h1.gender,h2.gender
        FROM hampster h1, hampster h2,partner p
        INNER JOIN partner on h1.ID = partner.ID1
        INNER JOIN children on h2.ID = children.ID1
WHERE h1.id = p.id1
  AND h2.id = p.id2
  AND h1.gender = h2.gender
  AND EXISTS (SELECT c.id1
            FROM children c
            WHERE c.id1 = p.id1
             OR  c.id1 = p.id2)
ORDER BY h1.gender, h1.name;

This is created when I add hampsters h2 into my query. My goal is to use inner join to combine two instances of the hamspter table and still use 'h1' and 'h2' to refer to them.

This is the expected output from the query

h1.name    h2.name gender
Alex        King    0
Grant       Alex    0
Jack        Grant   0
Cathy       Amy     1
Trish       Amy     1

Answer 1

You missing a table alias in where condition, server didn't know which ID column your using.

Try this one :

where h1.ID = 101