Check out example codes for "sql join one to many". It will help you in understanding the concepts better.

Code Example 1

SELECT   *
FROM        Parent P
INNER JOIN  Child  C
    ON      C.ParentId = P.ParentId

Code Example 2

SELECT      P.Name
            , P.Address
            , SUM(C.Amount)
FROM        Parent P
INNER JOIN  Child  C
    ON      C.ParentId = P.ParentId
GROUP BY    P.Name
            , P.Address

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