join column

基本解释

If you do not specify the Join column, JPA will attempt to resolve the keys based on a naming scheme.
如果您未指定 Join 列，JPA 将根据命名方案尝试解析这些键。
It then reads from the outer table BAD_CREDIT using the SHIP operator, hashing the join column values, and checking in the lookup table generated for the inner table.
然后，它使用 SHIP 操作符读外表 BAD_CREDIT，散列连接列的值，并检查为内表生成的查找表。
If there is an index on the join column, the costs will be significantly less; otherwise the database server must perform table scans for all tables, both outer and inner tables.
如果连接列上有一个索引，那么其成本会相当低；否则，数据库服务器就必须对所有表（外部和内部表）执行表扫描。

Bob Mondello, NPR's film and art's critic will join us to talk a little bit more about that in the new column, Brother's Film.
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