查询
查询不能只查tag标签,一定要加上fields。
如:select val,"班组" FROM "测试表" WHERE dev = 'cs123' and time> now() - 20m
直接写:select "班组" FROM "测试表" WHERE dev = 'cs123' and time> now() - 20m ,数据库不会显示数据。
查询
查询不能只查tag标签,一定要加上fields。
如:select val,"班组" FROM "测试表" WHERE dev = 'cs123' and time> now() - 20m
直接写:select "班组" FROM "测试表" WHERE dev = 'cs123' and time> now() - 20m ,数据库不会显示数据。