[DERBY-4719] Define consistent Derby data source behavior

• Type: Task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 10.7.1.1
• Component/s: Javadoc, JDBC, Network Client
• Labels: derby_triage10_9
• Urgency: Normal
• Bug behavior facts: Embedded/Client difference
• Assignee: Unassigned
• Reporter: Kristian Waagan
• Created: 28/Jun/10 13:07
• Updated: 11/Sep/14 18:40

Description

The behavior of the various data source implementations in Derby isn't consistent.

As a starting point, from the thread [1] on derby-dev:

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Hi,

I have been investigating how the various Derby data source implementations behave when it comes to [bean] properties.
Properties and attributes are used interchangeably, and I'll be using the following abbreviations:
o DS-[E|C] the "normal" data souce embedded/client
o CP-[E|C] ConnectionPoolDataSource embedded/client
o XA-[E|C] XADataSource embedded/client

Here are some of the current issues:
1) CP-C and XA-C effectively ignore the connection attribute string for certain attributes (those who have individual setters, DERBY-4067)
2) *-E don't update the internal property state based on the connection attribute string (i.e. specifying ";user=myuser" won't change the return value of getUser() after connect).
3) Only some of the properties are updated from the connection attribute string. This is as expected, but it is confusing that for instance 'traceDirectory' is updated and 'traceLevel' isn't.
4) *-C has 'APP' as the default user, *-E has <null>.
5) Some property setters accept all values, others throw an exception if the value is invalid.

I don't think all these issues should be fixed, but I'd like to fix (1), as it has caused some trouble in the past (i.e., user not understanding why the settings aren't taking effect).
There are several possible fixes for (1):
1a) Make CP-C and XA-C process the connection attribute string to update the internal state.
1b) Make DS-C ignore the connection attribute string (may break existing deployments).
1c) Throw exception if a property with a setter is specified in the connection attribute string.

I don't care that much about which solution is chosen, but I'd prefer that the various data sources are consistent. For instance, it would be nice if a user could swap ClientDataSource with ClientConnectionPoolDataSource without having to change the data source definition. For instance, doing this today with "ssl=basic" in the connection attribute string would make DS-C connect with SSL, but CP-C would connection without SSL.

We have this wording in the JavaDoc for ClienBaseDataSource.setConnectionAttributes(String):
"Set this property to pass in more Derby specific connection URL attributes.
Any attributes that can be set using a property of this DataSource implementation (e.g user, password) should not be set in connectionAttributes. Conflicting settings in connectionAttributes and properties of the DataSource will lead to unexpected behaviour."

Any opinions or questions on any of this?

Regards,

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[1] http://old.nabble.com/Derby-data-sources-to28692616.html#a28692616

Issue Links

• is related to: DERBY-4067 ClientConnectionPoolDataSource.getPooledConnection and ClientXADataSource.getXAConnection ignore connection attributes