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https://issues.apache.org/jira/browse/HIVE-5060?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13739437#comment-13739437
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Amareshwari Sriramadasu commented on HIVE-5060:
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@Henry, HIVE-4569 adds another api to call execute asynchronously. After that,
current code of jdbc driver should just work.
If we have a synchronous api, the clients such as jdbc can fetch results after
the execute immediately without bombarding the server with so many get-status
calls. So, i definitely see the need for two apis.
> JDBC driver assumes executeStatement is synchronous
> ---------------------------------------------------
>
> Key: HIVE-5060
> URL: https://issues.apache.org/jira/browse/HIVE-5060
> Project: Hive
> Issue Type: Bug
> Components: JDBC
> Affects Versions: 0.11.0
> Reporter: Henry Robinson
> Fix For: 0.11.1, 0.12.0
>
> Attachments:
> 0001-HIVE-5060-JDBC-driver-assumes-executeStatement-is-sy.patch
>
>
> The JDBC driver seems to assume that {{ExecuteStatement}} is a synchronous
> call when performing updates via {{executeUpdate}}, where the following
> comment on the RPC in the Thrift file indicates otherwise:
> {code}
> // ExecuteStatement()
> //
> // Execute a statement.
> // The returned OperationHandle can be used to check on the
> // status of the statement, and to fetch results once the
> // statement has finished executing.
> {code}
> I understand that Hive's implementation of {{ExecuteStatement}} is blocking
> (see https://issues.apache.org/jira/browse/HIVE-4569), but presumably other
> implementations of the HiveServer2 API (and I'm talking specifically about
> Impala here, but others might have a similar concern) should be free to
> return a pollable {{OperationHandle}} per the specification.
> The JDBC driver's {{executeUpdate}} is as follows:
> {code}
> public int executeUpdate(String sql) throws SQLException {
> execute(sql);
> return 0;
> }
> {code}
> {{execute(sql)}} discards the {{OperationHandle}} that it gets from the
> server after determining whether there are results to be fetched.
> This is problematic for us, because Impala will cancel queries that are
> running when a session executes, but there's no easy way to be sure that an
> {{INSERT}} statement has completed before terminating a session on the client.
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