ORACLE KEEP (DENSE_RANK FIRST/LAST) 聚合子句 迁移 shentong 7 怎么改

兼容性判定

怎么改

需按命中位置逐条评估改写

判定说明

能力矩阵暂未声明该特征，按未覆盖处理并降低置信度，建议 PoC 复核

库侧 / 应用侧路径

推荐路线：app_side。验证建议：并列第一（tie）用例必测：KEEP 聚合与窗口取单行的结果差异

规则样例

SELECT MAX(sal) KEEP (DENSE_RANK FIRST ORDER BY hire_date) FROM emp

SELECT dept, MIN(sal) KEEP (DENSE_RANK LAST ORDER BY ver) FROM emp GROUP BY dept

SELECT DENSE_RANK() OVER (ORDER BY sal) FROM emp

参考来源

• https://www.shentongdata.com/index.php/download/list-26
• https://opengauss.org/en/user-practice/dbv/shentongdata/
• https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/FIRST.html