Hi Michael,
Michael Bouschen wrote:
>Hi Tom,
>
>
>>Hi Michael,
>>
>> I think I did a poor job or explaining what I was hoping for in my
>>last email. I appologize. Here's what I was hoping for. Please let
>>me know if I am missing something as far as what is possible or what
>>makes sense to you.
>>
>>1. Expression.today() should result in the same thing as
>>currentDateDate (CURRENT_DATE, I think)
>>
>>
>Now I know why I'm confused :-). There is no method today() in class
>Expression. Only class ExpressionOperator has a method today(). And I
>think it would be confusing to add Expression.today() with an semantics
>(CURRENT_DATE) that is different from what ExpressionOperator.today()
>currently implements (CURRENT_TIMESTAMP). What do you think?
>
>
I agree. Sorry about the confusion.
-Tom
>>2. We should add a.currentTimestamp() to the Expression class.
>>
>>
>OK.
>
>
>>Other than that, everything looks good.
>>
>>
>Thanks!
>
>Regards Michael
>
>
>>-Tom
>>
>>Michael Bouschen wrote:
>>
>>
>>
>>>Hi Tom,
>>>
>>>attached you find a new version of my updates.
>>>
>>>I added a new method currentTimeStamp() to ExpressionOperator and
>>>ExpressionOperator.today() simply calls that new method. The
>>>attached jar also includes the tests I plan to add to
>>>entity-persistence-tests.
>>>
>>>Thanks!
>>>
>>>Regards Michael
>>>
>>>
>>>
>>>
>>>
>>>
>>>>Hi Michael,
>>>>
>>>>Michael Bouschen wrote:
>>>>
>>>>
>>>>
>>>>
>>>>>Hi Tom,
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>Hi Michael,
>>>>>>
>>>>>>Some comments:
>>>>>>
>>>>>>- can we map today() to the same things as currentDate() and add a
>>>>>>currentTimeStampMethod()?
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>Do you mean the methods in class Expression or the constants in
>>>>>ExpressionOperator? In the current code the Expression method
>>>>>currentDate() uses ExpressionOperator.Today and represents
>>>>>CURRENT_TIMESTAMP.
>>>>>
>>>>>
>>>>>
>>>>Lets just change the ExpressionOperator code. Since
>>>>ExpressionOperator.today() already exists, I am hesitant to remove
>>>>it, and I think that in order to change Expression, we would have to
>>>>do just that.
>>>>
>>>>
>>>>
>>>>
>>>>>Method currentDateDate() uses ExpressionOperator.currentDate and
>>>>>represents CURRENT_DATE.
>>>>>
>>>>>I agree it would be cleaner to have a method currentTimeStamp()
>>>>>representing CURRENT_TIMESTAMP, so I can add this. Do you also
>>>>>propose to change the implementation of currentDate() to represent
>>>>>CURRENT_DATE and then remove method currentDateDate()?
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>I am a little concerned about changing the way those methods work
>>>>for backwards compatibility reasons. My vote is to keep them as
>>>>they are.
>>>>
>>>>
>>>>
>>>>
>>>>>
>>>>>
>>>>>
>>>>>>- In DateFunctionNode, there are some if statements without
>>>>>>braces around the contents. Our current coding convention
>>>>>>requires the braces. Could you please add them.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>OK.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>I am working on running the tests on DB2. I will let you know the
>>>>>>results, but I think you can go ahead and check-in.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>OK.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>Are you adding a test?
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>Yes, I will add test cases that use the different JPQL date
>>>>>functions in a bulk update.
>>>>>
>>>>>Thanks!
>>>>>
>>>>>Regards Michael
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>-Tom
>>>>>>
>>>>>>Michael Bouschen wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>>Hi Tom,
>>>>>>>
>>>>>>>unfortunately derby does not accept assigning a timestamp to a
>>>>>>>time column. When using the currentDate Expression for
>>>>>>>CURRENT_TIME my test runs into similar exception as Mitesh
>>>>>>>mentioned below:
>>>>>>>SqlException: Columns of type 'TIME' cannot hold values of type
>>>>>>>'TIMESTAMP'. Error Code: -1
>>>>>>>Call:UPDATE EMPLOYEE_TBL SET TESTTIME = CURRENT TIMESTAMP
>>>>>>>
>>>>>>>I propose to introduce a new method currentTime to the Expression
>>>>>>>class and use this for the JPQL date function CURRENT_TIME. Class
>>>>>>>ExpressionOperator implements the default SQL for the date/time
>>>>>>>ExpressionOperator methods today(), currentDate() and
>>>>>>>currentTime(). I propose to change this default to the SQL 92
>>>>>>>date functions CURRENT_DATE, CURRENT_TIME and CURRENT_TIMESTAMP.
>>>>>>>I adapted some of the DatabasePlatform subclasses accordingly,
>>>>>>>but I was not able to do this for all the platforms. It would be
>>>>>>>great if you could take a look.
>>>>>>>
>>>>>>>I was able to successfully run a modified version of Mitesh's
>>>>>>>test case running all the date functions (CURRENT_DATE,
>>>>>>>CURRENT_TIME and CURRENT_TIMESTAMP) for the databases: Derby,
>>>>>>>Oracle 9, SQL Server 2000 and MySQL 5.
>>>>>>>
>>>>>>>You find my changes attached, thanks!
>>>>>>>
>>>>>>>Regards Michael
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>Hi Michael,
>>>>>>>>
>>>>>>>>I think currentDate() should work for CURRENT_TIME.
>>>>>>>>
>>>>>>>>-Tom
>>>>>>>>
>>>>>>>>Michael Bouschen wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>>Hi Mitesh, hi Tom,
>>>>>>>>>
>>>>>>>>>good catch!
>>>>>>>>>
>>>>>>>>>I'll take a look at changing the query compiler. What is the
>>>>>>>>>correct mapping for the JPQL function CURRENT_TIME? Can I use
>>>>>>>>>currentDate() since currentDateDate() does not include the time
>>>>>>>>>portion?
>>>>>>>>>
>>>>>>>>>Mitesh, could you do a me favor and file an issue for this?
>>>>>>>>>Please assign it to me.
>>>>>>>>>
>>>>>>>>>Regards Michael
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>>Hi Mitesh,
>>>>>>>>>>
>>>>>>>>>>You are correct. To get the current timestamp, currentDate()
>>>>>>>>>>should be used.
>>>>>>>>>>
>>>>>>>>>>-Tom
>>>>>>>>>>
>>>>>>>>>>Mitesh Meswani wrote:
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>>Hi Michael,
>>>>>>>>>>>The current code for query compiler maps all of these
>>>>>>>>>>>functions to Expression#currentDateDate(). Some databases(for
>>>>>>>>>>>example derby) distinguish between a TIMESTAMP type and DATE
>>>>>>>>>>>type.
>>>>>>>>>>>For example the attached program which tries to update a
>>>>>>>>>>>TIMESTAMP field on derby using "Update Employee e set
>>>>>>>>>>>e.testTimeStamp = CURRENT_TIMESTAMP" generates sql "UPDATE
>>>>>>>>>>>EMPLOYEE_TBL SET TESTTIMESTAMP = CURRENT DATE" which is not
>>>>>>>>>>>accepted by Derby. It is obvious that we will need to map
>>>>>>>>>>>this functions to different expressions
>>>>>>>>>>>
>>>>>>>>>>>Tom,
>>>>>>>>>>>>From javadocs in Expression.java, it seems that CURRENT_DATE
>>>>>>>>>>>should be mapped to Expression#currentDateDate()
>>>>>>>>>>>(ExpressionOperator.currentDate) and CURRENT_TIMESTAMP should
>>>>>>>>>>>be mapped to Expression#currentDate()
>>>>>>>>>>>(ExpressionOperator.Today) . Is that correct?
>>>>>>>>>>>
>>>>>>>>>>>Thanks,
>>>>>>>>>>>Mitesh
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>
>>>
>>>
>>>
--
Tom Ware
Principal Software Engineer
Oracle Canada Inc.
Direct: (613) 783-4598
Email: tom.ware_at_oracle.com