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https://issues.apache.org/jira/browse/HBASE-18824?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Xiang Li updated HBASE-18824:
-----------------------------
Description:
Thanks to [Jerry and Chia-Ping Tsai's
comments|https://issues.apache.org/jira/browse/HBASE-18824?focusedCommentId=16167392&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-16167392]
to correct my wrong understanding.
The following documentation says that by default(when the timestamp is not
specified for Put or Delete), the system uses the server's
{{currentTimeMillis}}.
1. In chapter 27.2.4 Put
bq. Doing a put always creates a new version of a cell, at a certain timestamp.
{color:#205081}By default the system uses the server’s
currentTimeMillis{color}, ...
2. In chapter 27.2.5 Delete
bq. Deletes work by creating tombstone markers. For example, let’s suppose we
want to delete a row. For this you can specify a version, or else
{color:#205081}by default the currentTimeMillis is used.{color}...
It seems not consistent with the code. Because in the client side's code, when
timestamp is not specified, HConstants.LATEST_TIMESTAMP is used, which is
Long.MAX_VALUE, rather than {{System.currentTimeMillis()}}.
However, the documentation is correct, because on the server side, timestamp
of Put cell with HConstants.LATEST_TIMESTAMP will be replaced with server's
{{currentTimeMillis}}.
So we decide to add more comments to HConstants.LATEST_TIMESTAMP to help the
new comers steer clear of the confusion.
was:
Thanks to [Jerry and Chia-Ping Tsai's
comments|https://issues.apache.org/jira/browse/HBASE-18824?focusedCommentId=16167392&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-16167392]
to correct my wrong understanding.
The following documentation says that by default(when the timestamp is not
specified for Put or Delete), the system uses the server's
{{currentTimeMillis}}.
1. In chapter 27.2.4 Put
bq. Doing a put always creates a new version of a cell, at a certain timestamp.
{color:#205081}By default the system uses the server’s
currentTimeMillis{color}, ...
2. In chapter 27.2.5 Delete
bq. Deletes work by creating tombstone markers. For example, let’s suppose we
want to delete a row. For this you can specify a version, or else
{color:#205081}by default the currentTimeMillis is used.{color}...
It seems not consistent with the code. Because in the client side's code, when
timestamp is not specified, HConstants.LATEST_TIMESTAMP is used, which is
Long.MAX_VALUE, rather than {{System.currentTimeMillis()}}.
However, the documentation is correct, because timestamp of Put cell having
HConstants.LATEST_TIMESTAMP will be replaced with server's
{{currentTimeMillis}}.
So we decide to add more comments to HConstants.LATEST_TIMESTAMP to help the
new comers steer clear of the confusion.
> Add meaningful comment to HConstants.LATEST_TIMESTAMP to explain why it is
> MAX_VALUE
> ------------------------------------------------------------------------------------
>
> Key: HBASE-18824
> URL: https://issues.apache.org/jira/browse/HBASE-18824
> Project: HBase
> Issue Type: Improvement
> Reporter: Xiang Li
> Assignee: Xiang Li
> Priority: Minor
>
> Thanks to [Jerry and Chia-Ping Tsai's
> comments|https://issues.apache.org/jira/browse/HBASE-18824?focusedCommentId=16167392&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-16167392]
> to correct my wrong understanding.
> The following documentation says that by default(when the timestamp is not
> specified for Put or Delete), the system uses the server's
> {{currentTimeMillis}}.
> 1. In chapter 27.2.4 Put
> bq. Doing a put always creates a new version of a cell, at a certain
> timestamp. {color:#205081}By default the system uses the server’s
> currentTimeMillis{color}, ...
> 2. In chapter 27.2.5 Delete
> bq. Deletes work by creating tombstone markers. For example, let’s suppose we
> want to delete a row. For this you can specify a version, or else
> {color:#205081}by default the currentTimeMillis is used.{color}...
> It seems not consistent with the code. Because in the client side's code,
> when timestamp is not specified, HConstants.LATEST_TIMESTAMP is used, which
> is Long.MAX_VALUE, rather than {{System.currentTimeMillis()}}.
> However, the documentation is correct, because on the server side, timestamp
> of Put cell with HConstants.LATEST_TIMESTAMP will be replaced with server's
> {{currentTimeMillis}}.
> So we decide to add more comments to HConstants.LATEST_TIMESTAMP to help the
> new comers steer clear of the confusion.
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