fix read from ColumnFileBigReader

[lidezhu]

What problem does this PR solve?

Issue Number: ref #5252

Problem Summary: Currently ColumnFileBigReader::readNextBlock doesn't work normally when just read two columns, because we never call readNextBlock when we just need read pk and version column.
But after support fast mode, there is a chance that the previous scenario happens. So we must fix it.

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• JaySon-Huang
• hongyunyan

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
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[lidezhu]

/cc @hongyunyan

[lidezhu]

/rebuild

[lidezhu]

/run-all-tests

[sre-bot]

Coverage for changed files

Filename                           Regions    Missed Regions     Cover   Functions  Missed Functions  Executed       Lines      Missed Lines     Cover    Branches   Missed Branches     Cover
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ColumnFile/ColumnFileBig.cpp            74                 9    87.84%          12                 0   100.00%         184                20    89.13%          44                10    77.27%
ColumnFile/ColumnFileBig.h              27                 1    96.30%          11                 1    90.91%          43                 5    88.37%          10                 2    80.00%
tests/gtest_dm_column_file.cpp         329                61    81.46%           6                 0   100.00%         101                 0   100.00%         104                45    56.73%
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
TOTAL                                  430                71    83.49%          29                 1    96.55%         328                25    92.38%         158                57    63.92%

Coverage summary

Functions  MissedFunctions  Executed  Lines   MissedLines  Cover
18600      9570             48.55%    211934  96319        54.55%

full coverage report (for internal network access only)

[JaySon-Huang]

But after support fast mode, there is a chance that the previous scenario happens

To be more specific, is it mean that under normal mode, at least we read 3 columns <pk, tag, version>. But for fast mode, we may only read <pk, tag>. And this bug will make the select count(*) from t return the wrong result under fast mode?

[JaySon-Huang]

LGTM

[hongyunyan]

LGTM

[lidezhu]

But after support fast mode, there is a chance that the previous scenario happens

To be more specific, is it mean that under normal mode, at least we read 3 columns <pk, tag, version>. But for fast mode, we may only read <pk, tag>. And this bug will make the select count(*) from t return the wrong result?

Yes. In normal mode, we may read <pk, version> column to place delta index, but we use ColumnFileBigReader::readRows to do it. And when use ColumnFileBigReader::readNextBlock, we will read at least 3 columns <pk, tag, version>. So this bug doesn't affect normal mode.

[lidezhu]

/merge

[ti-chi-bot]

@lidezhu: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

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[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: c4882a5

[sre-bot]

Coverage for changed files

Filename                           Regions    Missed Regions     Cover   Functions  Missed Functions  Executed       Lines      Missed Lines     Cover    Branches   Missed Branches     Cover
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ColumnFile/ColumnFileBig.cpp            74                 9    87.84%          12                 0   100.00%         184                20    89.13%          44                10    77.27%
ColumnFile/ColumnFileBig.h              27                 1    96.30%          11                 1    90.91%          43                 5    88.37%          10                 2    80.00%
tests/gtest_dm_column_file.cpp         329                61    81.46%           6                 0   100.00%         101                 0   100.00%         104                45    56.73%
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
TOTAL                                  430                71    83.49%          29                 1    96.55%         328                25    92.38%         158                57    63.92%

Coverage summary

Functions  MissedFunctions  Executed  Lines   MissedLines  Cover
18631      9389             49.61%    212496  94835        55.37%

full coverage report (for internal network access only)

[lidezhu]

/run-integration-test

[ti-chi-bot]

@lidezhu: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[sre-bot]

Coverage for changed files

Filename                           Regions    Missed Regions     Cover   Functions  Missed Functions  Executed       Lines      Missed Lines     Cover    Branches   Missed Branches     Cover
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ColumnFile/ColumnFileBig.cpp            74                 9    87.84%          12                 0   100.00%         184                20    89.13%          44                10    77.27%
ColumnFile/ColumnFileBig.h              27                 1    96.30%          11                 1    90.91%          43                 5    88.37%          10                 2    80.00%
tests/gtest_dm_column_file.cpp         329                61    81.46%           6                 0   100.00%         101                 0   100.00%         104                45    56.73%
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
TOTAL                                  430                71    83.49%          29                 1    96.55%         328                25    92.38%         158                57    63.92%

Coverage summary

Functions  MissedFunctions  Executed  Lines   MissedLines  Cover
18631      9391             49.59%    212496  94899        55.34%

full coverage report (for internal network access only)