Java android中模棱两可的列名
如果我有两个带列的表Java android中模棱两可的列名,java,android,sqlite,Java,Android,Sqlite,如果我有两个带列的表 TABLE 1: [_id,info] TABLE 2: [_id,date] 并进行联接如何解决结果游标中的_id列的不明确性,并仅访问表2的_id列?通常,如果列名不明确,可以使用别名来区分它们 SELECT t1._id as t1_id, t2._id as t2_id FROM ... JOIN ... 在这种情况下,我猜您是在_id字段等于的情况下加入的。然后您只能选择一次: SELECT T2._id as id T1.i
TABLE 1: [_id,info]
TABLE 2: [_id,date]
并进行联接如何解决结果游标中的_id列的不明确性,并仅访问表2的_id列?通常,如果列名不明确,可以使用别名来区分它们
SELECT
t1._id as t1_id,
t2._id as t2_id
FROM ...
JOIN ...
在这种情况下,我猜您是在_id字段等于的情况下加入的。然后您只能选择一次:
SELECT
T2._id as id
T1.info,
T2.date
FROM table1 AS T1
JOIN table2 AS T2
ON T1._id = T2._id
通常,如果列名不明确,可以使用别名来区分它们
SELECT
t1._id as t1_id,
t2._id as t2_id
FROM ...
JOIN ...
在这种情况下,我猜您是在_id字段等于的情况下加入的。然后您只能选择一次:
SELECT
T2._id as id
T1.info,
T2.date
FROM table1 AS T1
JOIN table2 AS T2
ON T1._id = T2._id
您可以发布您的查询吗?该查询与您在答案中发布的查询类似,但没有别名。谢谢你的回答!您可以发布您的查询吗?该查询与您在答案中发布的查询类似,但没有别名。谢谢你的回答!