[ https://issues.apache.org/jira/browse/PHOENIX-6888?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kadir Ozdemir reassigned PHOENIX-6888: -------------------------------------- Assignee: Kadir Ozdemir > Fixing TTL and Max Lookback Issues for Phoenix Tables > ----------------------------------------------------- > > Key: PHOENIX-6888 > URL: https://issues.apache.org/jira/browse/PHOENIX-6888 > Project: Phoenix > Issue Type: Bug > Affects Versions: 5.1.3 > Reporter: Kadir Ozdemir > Assignee: Kadir Ozdemir > Priority: Major > > In HBase, the unit of data is a cell and data retention rules are executed at > the cell level. These rules are defined at the column family level. Phoenix > leverages the data retention features of HBase and exposes them to its users > to provide its TTL feature at the table level. However, these rules (since > they are defined at the cell level instead of the row level) results in > partial row retention that in turn creates data integrity issues at the > Phoenix level. > Similarly, Phoenix’s max lookback feature leverages HBase deleted data > retention capabilities to preserve deleted cells within a configurable max > lookback. This requires two data retention windows, max lookback and TTL. One > end of these windows is the current time and the end is a moment in the past > (i.e., current time minus the window size). Typically, the max lookback > window is shorter than the TTL window. In the max lookback window, we would > like to preserve the complete history of mutations regardless of how many > cell versions these mutations generated. In the remaining TTL window outside > the max lookback, we would like to apply the data retention rules defined > above. However, HBase provides only one data retention window. Thus, the max > lookback window had to be extended to become TTL window and the max lookback > feature results in unwantedly retaining deleted data for the maximum of max > lookback and TTL periods. > This Jira is to fix both of these issues. -- This message was sent by Atlassian Jira (v8.20.10#820010)