And if you don't specify these as readonly and you try to save the object, the whole thing bombs. If you need this functionality, why not create a database view to load the object model from?
-----Original Message----- From: Bobby Lawrence [mailto:[EMAIL PROTECTED] Sent: Monday, January 24, 2005 8:32 AM To: OJB Users List Subject: Re: remove table alias in generated SQL? Not having an alias would allow you to use functions and string literals. You could specify a string literal in the field-descriptor like this: <field-descriptor name="myField" column="' 'a string literal' "> This would give you the same value for every class instance, which might not seem that useful at first, but this is exactly what I needed in my project for a brief time. At the time, I was expecting values from the database where the field did not exist yet and I needed something to test. You could also specify functions in the field-descriptor like this: <field-descriptor name="wholeName" column="CONCAT(CONCAT(firstname, ' ', lastname) AS wholename"> If using an Oracle database, this would concatenate the first and last names to give you a whole name. Another example on concatenation w/ Oracle without using the function: <field-descriptor name="wholeName" column="firstname || ' ' || lastname AS wholename"> All of these should be possible if OJB didn't use table aliases in its generated SQL statements. What IS the benefit of using an alias? Jakob Braeuchi wrote: > hi bobby, > > i still do not get the benefit of not using an alias. could you please > post a sample ? > > jakob > > Bobby Lawrence schrieb: > >> Well - it seems that the alias is not needed. >> If the class only goes to one table for its data, why does the table >> need an alias? >> If an alias was not used, you could specify string literals for a >> column name. >> >> >> Jakob Braeuchi wrote: >> >>> hi, >>> >>> ojb should always use the alias in front of the column name. if it >>> does not, it could probably not translate the attribute name into a >>> column name. >>> >>> btw: what exactly is the problem with the alias ?? >>> >>> jakob >>> >>> Vesely, Max [IT] schrieb: >>> >>>> Bobby, >>>> >>>> I was able to do it by listing field names in a ReportQuery object. >>>> It also won't append table alias in front of the column name in >>>> this case. >>>> >>>> Max. >>>> >>>> -----Original Message----- >>>> From: Bobby Lawrence [mailto:[EMAIL PROTECTED] Sent: >>>> Thursday, January 20, 2005 5:38 PM >>>> To: ojb-user@db.apache.org >>>> Subject: remove table alias in generated SQL? >>>> >>>> Is there a way to tell OJB to not use the table alias in front of >>>> the column names when it generates SQL? >>>> Currently, when you specifiy that a class comes from <tableA> and a >>>> field of that class comes from <fieldA>, OJB executes the following >>>> SQL: >>>> SELECT A0.<fieldA> FROM <tableA> A0 >>>> >>>> If you can't map one class to multiple tables, I don't see why this >>>> is necessary. >>>> Is there any way around this? >>>> >>>> Instead of mapping a field to a specific column, I want to map it >>>> to a string literal so that it always has the same value for the >>>> class. >>>> >>>> Ex. <field-descriptor column= 'some literal' AS myColumn"> >>>> >>>> -- Bobby >>>> >>>> >>>> >>>> >>>> >>>> ------------------------------------------------------------------- >>>> -- To unsubscribe, e-mail: [EMAIL PROTECTED] >>>> For additional commands, e-mail: [EMAIL PROTECTED] >>>> >>>> >>>> >>>> ------------------------------------------------------------------- >>>> -- To unsubscribe, e-mail: [EMAIL PROTECTED] >>>> For additional commands, e-mail: [EMAIL PROTECTED] >>>> >>>> >>> >>> -------------------------------------------------------------------- >>> - To unsubscribe, e-mail: [EMAIL PROTECTED] >>> For additional commands, e-mail: [EMAIL PROTECTED] >>> >> > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > -- ---------------------------- Bobby Lawrence MIS Application Developer Jefferson Lab (www.jlab.org) Email: [EMAIL PROTECTED] Office: (757) 269-5818 Pager: (757) 584-5818 ---------------------------- --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
