Create relationship
CREATE RELATIONSHIP 在 Direct Query 应用程序数据模型中指定新的表和列关系。
CREATE RELATIONSHIP 只能在 Direct Query 应用程序中使用。它前面必须有 section directquery 部分。
语法：
CREATE RELATIONSHIP (OUTER|INNER) JOINED] TableName, [(OUTER|INNER) JOINED] TableName ON ConditionExpression ;
信息注释
如果未指定表的 outer|inner joined 限定符，则默认为 inner joined。
信息注释
对于 TableName，可以使用带引号的名称引用。例如，( IDENTIFIER | LITERAL_STRING | LITERAL_FIELD | LITERAL_NUMBER))。
示例：
CREATE RELATIONSHIP BETWEEN T1,T2 ON A = C;
CREATE RELATIONSHIP
BETWEEN OUTER JOINED T2, INNER JOINED T3
ON (D = E or (D is null and E is null));
BETWEEN OUTER JOINED T2, INNER JOINED T3
ON (D = E or (D is null and E is null));