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Original file line number Diff line number Diff line change
Expand Up @@ -38,9 +38,7 @@ INSERT INTO <TABLE_NAME> [(COLUMN_NAME[, COLUMN_NAME]*)]? VALUES (COLUMN_VALUE[,
3. If no timestamp is provided, the system will use the current time (`now()`).
4. If a column value does not exist for the identified device, the insertion will overwrite any existing `null` values with the new data.
5. If a column value already exists for the identified device, a new insertion will update the column with the new value.
6. For duplicate timestamps:
1. Columns with `null` values at the original timestamp will be updated.
2. Columns with non-`null` values at the original timestamp will retain their original values.
6. Writing duplicate timestamps will update the values in the columns corresponding to the original timestamps.

Since attributes generally do not change over time, it is recommended to update attribute values using the `UPDATE` statement described below,Please refer to the following [Data Update](#2-data-updates).

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Original file line number Diff line number Diff line change
Expand Up @@ -38,9 +38,7 @@ INSERT INTO <TABLE_NAME> [(COLUMN_NAME[, COLUMN_NAME]*)]? VALUES (COLUMN_VALUE[,
3. If no timestamp is provided, the system will use the current time (`now()`).
4. If a column value does not exist for the identified device, the insertion will overwrite any existing `null` values with the new data.
5. If a column value already exists for the identified device, a new insertion will update the column with the new value.
6. For duplicate timestamps:
1. Columns with `null` values at the original timestamp will be updated.
2. Columns with non-`null` values at the original timestamp will retain their original values.
6. Writing duplicate timestamps will update the values in the columns corresponding to the original timestamps.

Since attributes generally do not change over time, it is recommended to update attribute values using the `UPDATE` statement described below,Please refer to the following [Data Update](#2-data-updates).

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Original file line number Diff line number Diff line change
Expand Up @@ -38,7 +38,7 @@ INSERT INTO <TABLE_NAME> [(COLUMN_NAME[, COLUMN_NAME]*)]? VALUES (COLUMN_VALUE[,
3. 未包含时间戳,系统将使用当前时间 `now()` 进行填充。
4. 若当前设备(由标识信息定位)不存在该属性列的值,执行写入操作将导致原有的空值(NULL)被写入的数据所替代。
5. 若当前设备(由标识信息定位)已有属性列的值,再次写入相同的属性列时,系统将更新该属性列的值为新数据。
6. 写入重复时间戳,原时间戳为null的列会被更新,原不为null的列,保留原来列的值
6. 写入重复时间戳,原时间戳对应列的值会更新

由于属性一般并不随时间的变化而变化,因此推荐以 update 的方式单独更新属性值,参见下文 [数据更新](#数据更新)。

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Original file line number Diff line number Diff line change
Expand Up @@ -38,7 +38,7 @@ INSERT INTO <TABLE_NAME> [(COLUMN_NAME[, COLUMN_NAME]*)]? VALUES (COLUMN_VALUE[,
3. 未包含时间戳,系统将使用当前时间 `now()` 进行填充。
4. 若当前设备(由标识信息定位)不存在该属性列的值,执行写入操作将导致原有的空值(NULL)被写入的数据所替代。
5. 若当前设备(由标识信息定位)已有属性列的值,再次写入相同的属性列时,系统将更新该属性列的值为新数据。
6. 写入重复时间戳,原时间戳为null的列会被更新,原不为null的列,保留原来列的值
6. 写入重复时间戳,原时间戳对应列的值会更新

由于属性一般并不随时间的变化而变化,因此推荐以 update 的方式单独更新属性值,参见下文 [数据更新](#数据更新)。

Expand Down