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Kathey Marsden commented on DERBY-118: -------------------------------------- I think we should not lift any SQL restrictions without very good reason If there is a compelling reason to violate the standard (or violate it further) the proposal is to do so it should be put into a separate Jira and the case made there if there are other SQL compliant changes being made under this issue. > Lift some DB2 restrictions on DEFAULT values [was: Allow any build-in > function as default values in table create for columns] > ----------------------------------------------------------------------------------------------------------------------------- > > Key: DERBY-118 > URL: https://issues.apache.org/jira/browse/DERBY-118 > Project: Derby > Issue Type: Improvement > Components: SQL > Reporter: Bernd Ruehlicke > Assignee: Dag H. Wanvik > Priority: Minor > Attachments: derby-118-all-defaults.diff, derby-118-longvarchar.diff, > derby-118.diff, derby-118.stat, derby-118b.diff, derby-118b.stat, > derby-118c.diff, derby-118c.stat > > > It is ok in ij to do a values char(current_date) but is is not allowed to > use char(current_date) as default value for clolumns; like for example > CREATE TABLE DOSENOTWORK (num int, created_by varchar(40) default user, > create_date_string varchar(40) default char(current_date)) > Request: It should be allowed to use any build-in function which return a > valid type as part of the default value spec. > There was a e-mail thread for this and the core content/answer was: > Bernd Ruehlicke wrote: > > > > CREATE TABLE DOSENOTWORK (num int, created_by varchar(40) default > > user, create_date_string varchar(40) default char(current_date)) > > > > give an error as below - any idea why ?!??! > > > The rules for what is acceptable as a column default in Derby say that the > only valid functions are datetime functions. > The logic that enforces this can be seen in the "defaultTypeIsValid" method > of the file: > ./java/engine/org/apache/derby/impl/sql/compile/ColumnDefinitionNode.java > The Derby Reference Manual also states this same restriction (albeit rather > briefly): > ---- > Column Default > For the definition of a default value, a ConstantExpression is an expression > that does not refer to any table. It can include constants, date-time special > registers, current schemas, users, and null. > ---- > A "date-time special register" here means a date-time function such as > "date(current_date)" in your first example. > Since the function "char" is NOT a date-time function, it will throw an error. > I believe this restriction was put in place as part of the "DB2 > compatibility" work was that done in Cloudscape a while back. > Hope that answers your question, > Army -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira