[IMPALA-10571] ImpalaJdbcClient might silently choose a different driver than the one specified

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Impala 4.0.0
• Epic Color: ghx-label-3
• Assignee: Zoltán Borók-Nagy
• Reporter: Zoltán Borók-Nagy
• Created: 09/Mar/21 15:25
• Updated: 10/Mar/21 16:47
• Resolved: 10/Mar/21 16:47

Description

I was experimenting with drivers while running into this issue.

I tried to do some testing with a custom JDBC driver with the following command:

bin/run-jdbc-client.sh -d "my.impala.jdbc.Driver" -t NOSASL -q "select 1"

The script outputted:

Using JDBC Driver Name: my.impala.jdbc.Driver
Connecting to: jdbc:impala://localhost:21050
Executing: select sleep(12000)
----[START]----
1
----[END]----

However, after some debugging I figured out that ImpalaJdbcClient actually used org.apache.hive.jdbc.HiveDriver. It was because the specified driver didn't accept the default connection string (jdbc:hive2://...), therefore the HiveDriver was being used.

I think instead of silently choosing a different driver, ImpalaJdbcClient should raise an error and tell the user to specify the connection string as well.