This is an automated email from the ASF dual-hosted git repository. qiaojialin pushed a commit to branch add_delete_doc in repository https://gitbox.apache.org/repos/asf/incubator-iotdb.git
commit 2b3209d0dbcc91fbc79130cabf6bdc06715fce78 Author: qiaojialin <[email protected]> AuthorDate: Fri Apr 10 13:26:54 2020 +0800 update delete doc --- docs/SystemDesign/4-StorageEngine/6-DataManipulation.md | 17 ++++++++++------- .../SystemDesign/4-StorageEngine/6-DataManipulation.md | 16 ++++++++++------ .../db/engine/storagegroup/StorageGroupProcessor.java | 2 +- 3 files changed, 21 insertions(+), 14 deletions(-) diff --git a/docs/SystemDesign/4-StorageEngine/6-DataManipulation.md b/docs/SystemDesign/4-StorageEngine/6-DataManipulation.md index 60d6253..78dd676 100644 --- a/docs/SystemDesign/4-StorageEngine/6-DataManipulation.md +++ b/docs/SystemDesign/4-StorageEngine/6-DataManipulation.md @@ -70,14 +70,17 @@ Old data is automatically deleted by merging, see: * Corresponding interface * JDBC's execute interface, using delete SQL statements -* Main entrance: public void delete(String deviceId, String measurementId, long timestamp) StorageEngine.java - * Find the corresponding StorageGroupProcessor - * Find all TsfileProcessor affected - * Pre-write log - * Find all TsfileResources affected - * Record the point in time of deletion in the mod file - * If the file is not closed (the corresponding TsfileProcessor exists), delete the data in memory +Each StorageGroupProcessor maintains a ascending version for each partition, which is managed by SimpleFileVersionController. +Each memtable will apply a version when submitted to flush. After flushing to TsFile, a current position-version will added to TsFileMetadata. +This information will be used to set version to ChunkMetadata when query. +* main entrance: public void delete(String deviceId, String measurementId, long timestamp) StorageEngine.java + * Find the corresponding StorageGroupProcessor + * Find all impacted working TsFileProcessors to write WAL + * Find all impacted TsFileResources to record a Modification in its mods file, the Modification format is: path，deleteTime，version + * If the TsFile is not closed，get its TsFileProcessor + * If there exists the working memtable, delete data in it + * If there exists flushing memtable，record the deleted time in it for query.（Notice that the Modification is recorded in mods for these memtables） ## Data TTL setting diff --git a/docs/zh/SystemDesign/4-StorageEngine/6-DataManipulation.md b/docs/zh/SystemDesign/4-StorageEngine/6-DataManipulation.md index 8b60018..51f024b 100644 --- a/docs/zh/SystemDesign/4-StorageEngine/6-DataManipulation.md +++ b/docs/zh/SystemDesign/4-StorageEngine/6-DataManipulation.md @@ -71,13 +71,17 @@ * 对应的接口 * JDBC 的 execute 接口，使用delete SQL语句 +每个 StorageGroupProsessor 中针对每个分区会维护一个自增的版本号，由 SimpleFileVersionController 管理。 +每个内存缓冲区 memtable 在持久化的时候会申请一个版本号。持久化到 TsFile 后，会在 TsFileMetadata 中记录此 memtable 对应的 多个 ChunkGroup 的终止位置和版本号。 +查询时会根据此信息对 ChunkMetadata 赋 version。 + * 总入口: public void delete(String deviceId, String measurementId, long timestamp) StorageEngine.java - * 找到对应的 StorageGroupProcessor - * 找到受影响的所有TsfileProcessor - * 写写前日志 - * 找到受影响的所有TsfileResource - * 在mod文件中记录删除的时间点 - * 如果文件没有关闭（存在对应的TsfileProcessor），则删除内存中的数据 + * 找到对应的 StorageGroupProcessor + * 找到受影响的所有 working TsFileProcessor 记录写前日志 + * 找到受影响的所有 TsFileResource，在其对应的 mods 文件中记录一条记录：path，deleteTime，version + * 如果文件没有关闭，拿到对应的 TsFileProcessor + * 如果存在 working memtable：则删除内存中的数据 + * 如果存在 正在 flush 的 memtable，记录一条记录，查询时跳过删掉的数据（注意此时文件中已经为这些 memtable 记录了 mods） ## 数据TTL设置 diff --git a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java index d3afe72..27d0acf 100755 --- a/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java +++ b/server/src/main/java/org/apache/iotdb/db/engine/storagegroup/StorageGroupProcessor.java @@ -1149,7 +1149,7 @@ public class StorageGroupProcessor { // time partition to divide storage group long timePartitionId = StorageEngine.getTimePartition(timestamp); - // write log + // write log to impacted working TsFileProcessors logDeletion(timestamp, deviceId, measurementId, timePartitionId); Path fullPath = new Path(deviceId, measurementId);
