有两个表分别为tb_child(child_id,name),tb_cdc_child(child_id,username)tb_child的数据为(t1,jack)(t2,mary)两条，tb_cdc_child的数据为(t1,lee)(t2,tom)两条。现需做update操作,将tb_child中child_id与tb_cdc_child中child_id相同的那条数据的name字段更新为tb_cdc_child中对应数据的username字段。即更新过后的tb_child的数据变为(t1,lee)(t2,tom)能否用一句sql实现该功能
试一下这个：
update tb_child as a , tb_cdc_child as b set a.name=b.username where a.child_id=b.child_id;
update tb_child as a , tb_cdc_child as b set a.name=b.username where a.child_id=b.child_id
这个语句应该可以
update tb_child as a , tb_cdc_child as b set a.name=b.username where a.child_id=b.child_id
Update a,b set a.name=b.name where a.id=b.id