ttl is based on the timestamp of data point not the write time

src/UserGuide/Master/Table/Basic-Concept/TTL-Delete-Data.md

@@ -32,6 +32,7 @@ TTL values are specified in milliseconds, and once data exceeds its defined life
 1. TTL defines the expiration time of data in milliseconds, independent of the time precision configuration file.
 2. Modifying TTL settings can cause temporary variations in data accessibility.
 3. The system eventually removes expired data, though this process may involve some delay.。
+4. The TTL expiration check is based on the data point timestamp, not the write time.
 
 ## 2. Set TTL
 

src/UserGuide/Master/Tree/Basic-Concept/Operate-Metadata_apache.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/Master/Tree/Basic-Concept/Operate-Metadata_timecho.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/Master/Tree/Basic-Concept/TTL-Delete.md

@@ -26,7 +26,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/V1.3.x/Basic-Concept/Operate-Metadata_apache.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/V1.3.x/Basic-Concept/Operate-Metadata_timecho.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/V1.3.x/Basic-Concept/TTL-Delete.md

@@ -26,7 +26,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/dev-1.3/Basic-Concept/Operate-Metadata_apache.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/dev-1.3/Basic-Concept/Operate-Metadata_timecho.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/dev-1.3/Basic-Concept/TTL-Delete.md

@@ -26,7 +26,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/latest-Table/Basic-Concept/TTL-Delete-Data.md

@@ -32,6 +32,7 @@ TTL values are specified in milliseconds, and once data exceeds its defined life
 1. TTL defines the expiration time of data in milliseconds, independent of the time precision configuration file.
 2. Modifying TTL settings can cause temporary variations in data accessibility.
 3. The system eventually removes expired data, though this process may involve some delay.。
+4. The TTL expiration check is based on the data point timestamp, not the write time.
 
 ## 2. Set TTL
 

src/UserGuide/latest/Basic-Concept/Operate-Metadata_apache.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/latest/Basic-Concept/Operate-Metadata_timecho.md

@@ -248,7 +248,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/UserGuide/latest/Basic-Concept/TTL-Delete.md

@@ -26,7 +26,7 @@ IoTDB supports device-level TTL settings, which means it is able to delete old d
 
 The default unit of TTL is milliseconds. If the time precision in the configuration file changes to another, the TTL is still set to milliseconds.
 
-When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity.
+When setting TTL, the system will look for all devices included in the set path and set TTL for these devices. The system will delete expired data at the device granularity. The expiration check here is based on the data point timestamp, not the write time.
 After the device data expires, it will not be queryable. The data in the disk file cannot be guaranteed to be deleted immediately, but it can be guaranteed to be deleted eventually.
 However, due to operational costs, the expired data will not be physically deleted right after expiring. The physical deletion is delayed until compaction.
 Therefore, before the data is physically deleted, if the TTL is reduced or lifted, it may cause data that was previously invisible due to TTL to reappear.

src/zh/UserGuide/Master/Table/Basic-Concept/TTL-Delete-Data.md

@@ -30,6 +30,7 @@ IoTDB支持对表（table）级别设置数据保留时间（TTL），允许系
 1. TTL设置为毫秒，不受配置文件时间精度影响。
 2. TTL变更可能影响数据的可查询性。
 3. 系统最终会移除过期数据，但存在延迟。
+4. TTL 判断数据是否过期依据的是数据点时间，非写入时间。
 
 ## 2. 设置 TTL
 

src/zh/UserGuide/Master/Tree/Basic-Concept/Operate-Metadata_apache.md

@@ -151,7 +151,7 @@ IoTDB 支持对 device 级别设置数据保留时间（TTL），这使得 IoTDB
 
 TTL的默认单位为毫秒，如果配置文件中的时间精度修改为其他单位，设置ttl时仍然使用毫秒单位。
 
-当设置 TTL 时，系统会根据设置的路径寻找所包含的所有 device，并为这些 device 设置 TTL 时间，系统会按设备粒度对过期数据进行删除。
+当设置 TTL 时，系统会根据设置的路径寻找所包含的所有 device，并为这些 device 设置 TTL 时间，系统会按设备粒度对过期数据进行删除。请注意，此处是否过期判断依据的是数据点时间，不是写入时间。
 当设备数据过期后，将不能被查询到，但磁盘文件中的数据不能保证立即删除（会在一定时间内删除），但可以保证最终被删除。
 考虑到操作代价，系统不会立即物理删除超过 TTL 的数据，而是通过合并来延迟地物理删除。因此，在数据被物理删除前，如果调小或者解除 TTL，可能会导致之前因 TTL 而不可见的数据重新出现。
 系统中仅能设置至多 1000 条 TTL 规则，达到该上限时，需要先删除部分 TTL 规则才能设置新的规则

src/zh/UserGuide/Master/Tree/Basic-Concept/Operate-Metadata_timecho.md

@@ -151,7 +151,7 @@ IoTDB 支持对 device 级别设置数据保留时间（TTL），这使得 IoTDB
 
 TTL的默认单位为毫秒，如果配置文件中的时间精度修改为其他单位，设置ttl时仍然使用毫秒单位。
 
-当设置 TTL 时，系统会根据设置的路径寻找所包含的所有 device，并为这些 device 设置 TTL 时间，系统会按设备粒度对过期数据进行删除。
+当设置 TTL 时，系统会根据设置的路径寻找所包含的所有 device，并为这些 device 设置 TTL 时间，系统会按设备粒度对过期数据进行删除。请注意，此处是否过期判断依据的是数据点时间，不是写入时间。
 当设备数据过期后，将不能被查询到，但磁盘文件中的数据不能保证立即删除（会在一定时间内删除），但可以保证最终被删除。
 考虑到操作代价，系统不会立即物理删除超过 TTL 的数据，而是通过合并来延迟地物理删除。因此，在数据被物理删除前，如果调小或者解除 TTL，可能会导致之前因 TTL 而不可见的数据重新出现。
 系统中仅能设置至多 1000 条 TTL 规则，达到该上限时，需要先删除部分 TTL 规则才能设置新的规则

src/zh/UserGuide/Master/Tree/Basic-Concept/TTL-Delete.md

@@ -26,7 +26,7 @@ IoTDB 支持对 device 级别设置数据保留时间（TTL），这使得 IoTDB
 
 TTL的默认单位为毫秒，如果配置文件中的时间精度修改为其他单位，设置ttl时仍然使用毫秒单位。
 
-当设置 TTL 时，系统会根据设置的路径寻找所包含的所有 device，并为这些 device 设置 TTL 时间，系统会按设备粒度对过期数据进行删除。
+当设置 TTL 时，系统会根据设置的路径寻找所包含的所有 device，并为这些 device 设置 TTL 时间，系统会按设备粒度对过期数据进行删除。请注意，此处是否过期判断依据的是数据点时间，不是写入时间。
 当设备数据过期后，将不能被查询到，但磁盘文件中的数据不能保证立即删除（会在一定时间内删除），但可以保证最终被删除。
 考虑到操作代价，系统不会立即物理删除超过 TTL 的数据，而是通过合并来延迟地物理删除。因此，在数据被物理删除前，如果调小或者解除 TTL，可能会导致之前因 TTL 而不可见的数据重新出现。
 系统中仅能设置至多 1000 条 TTL 规则，达到该上限时，需要先删除部分 TTL 规则才能设置新的规则