android dao 错误是怎么回事？

Question

我构建了我的 android 项目，但是消息输出了以下错误，这个错误来自 android dao。

Error:(31, 19) error: mismatched input 'fromJson' expecting {<EOF>, ';', ',', K_ALTER, K_ANALYZE, K_ATTACH, K_BEGIN, K_COMMIT, K_CREATE, K_DELETE, K_DETACH, K_DROP, K_END, K_EXCEPT, K_EXPLAIN, K_FROM, K_GROUP, K_INSERT, K_INTERSECT, K_LIMIT, K_ORDER, K_PRAGMA, K_REINDEX, K_RELEASE, K_REPLACE, K_ROLLBACK, K_SAVEPOINT, K_SELECT, K_UNION, K_UPDATE, K_VACUUM, K_VALUES, K_WHERE, K_WITH, UNEXPECTED_CHAR}

Answer 1

这可能是您的 SQL 查询中的语法错误。

确保在连接查询（字符串）时在每行末尾放置一个空格。

@Query("SELECT c.username, c.first_name, c.last_name, r1.water_amount AS waterAmountLastMonth " +
       "FROM citizen c " +
       "INNER JOIN report r1 ON r1.date_month = :dateMonth " +
       "ORDER BY c.first_name ASC")