sql:select one row on join

        

        SELECT *
        FROM    AccountTransactions AS inv
                INNER JOIN [Accounts basic] a2 ON inv.AccountId = a2.ID
                JOIN ( SELECT   *
                       FROM     ( SELECT    *,
                                            ROW_NUMBER() OVER ( PARTITION BY AccountTransactionId ORDER BY ProcessDate ) AS RowId
                                  FROM      dbo.BillingTransactions
                                ) Tmp
                       WHERE    RowId = 1
                     ) b ON inv.TransactionId = b.AccountTransactionId
 

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