Tdengine语法顺序问题

Question

执行聚合查询时出现TDengine sql错误：

select avg(value) as gauge from table1 where ts >= now - 30d and ts <= now group by cluster interval(30d)

DB error: syntax error near "interval(30d);" (0.000552s)

这个sql中的语法错误是什么？

Answer 1

最后，在TDengine文档中可以找到：https://www.taosdata.com/docs/en/v2.0/taos-sql列出了的顺序，选择了条件语句。

SELECT select_expr [, select_expr ...]
    FROM {tb_name_list}
    [WHERE where_condition]
    [SESSION(ts_col, tol_val)]
    [STATE_WINDOW(col)]
    [INTERVAL(interval_val [, interval_offset]) [SLIDING sliding_val]]
    [FILL(fill_mod_and_val)]
    [GROUP BY col_list]
    [ORDER BY col_list { DESC | ASC }]
    [SLIMIT limit_val [SOFFSET offset_val]]
    [LIMIT limit_val [OFFSET offset_val]]
    [>> export_file];

因此，Group 应该放在Interval之后，下面是正确的sql：

select avg(value) as gauge from table1 where ts >= now - 30d and ts <= now interval(30d) group by cluster