[FLINK-13534][hive] Unable to query Hive table with decimal column

[lirui-apache]

What is the purpose of the change

Fix the issue that Flink cannot access Hive table with decimal columns.

Brief change log

• Avoid conversion between DataType and TypeInformation in several places. Because such conversions can lose type parameters.
• Add a test for decimal type.

Verifying this change

New test case.

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Yarn/Mesos, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no
• If yes, how is the feature documented? NA

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Automated Checks

Last check on commit 63c3d38 (Fri Aug 23 10:17:05 UTC 2019)

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Review Progress

• ❓ 1. The [description] looks good.
• ❓ 2. There is [consensus] that the contribution should go into to Flink.
• ❓ 3. Needs [attention] from.
• ❓ 4. The change fits into the overall [architecture].
• ❓ 5. Overall code [quality] is good.

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CI report:

• b2432f2 : FAILURE Build
• da1bae2 : SUCCESS Build
• 63c3d38 : SUCCESS Build

[lirui-apache]

@xuefuz @zjuwangg @bowenli86 please help review this PR. Thanks.

[zjuwangg]

LGTM.
It seems that we don't fix bugs but like code refactor, am I understanding right?

[lirui-apache]

LGTM.
It seems that we don't fix bugs but like code refactor, am I understanding right?

Yeah it's more like a refactor to make sure we stick to the new DataType.

[lirui-apache]

@xuefuz PR updated to test with non-zero-scale decimals. Please have a look. Thanks.

[xuefuz]

LGTM.

[bowenli86]

LGTM