Sybase Troubleshooting dbcc upgrade_object and Managing Select Statements in Views

CHAPTER 7 Troubleshooting

Determining whether select * should be changed in views

If dbcc upgrade_object reports the existence of select * in a view, compare the output of syscolumns for the original view to the output of the table, to determine whether columns have been added to or deleted from the table since the view was created.

For example, suppose you have the following statement:

create view all_emps as select * from employees

Before upgrading the all_emps view, use the following queries to determine the number of columns in the original view and the number of columns in the updated table:

select name from syscolumns where id = object_id("all_emps")

select name from syscolumns

where id = object_id("employees")

Compare the output of the two queries. If the table contains more columns than the view, and retaining the pre-upgrade results of the select * statement is important, change the select * statement to a select statement with specific column names. If the view was created from multiple tables, check the columns in all tables that comprise the view and rewrite the select statement if necessary.

Warning! Do not execute a select * statement from the view. Doing so upgrades the view and overwrites the information about the original column information in syscolumns.

Another way to determine the difference between the columns in the view and in the new tables is to run sp_help on both the view and the tables that comprise the view.

This comparison works only for views, not for other compiled objects. To determine whether select * statements in other compiled objects need to be revised, review the source text of each compiled object.

Using dbcc upgrade_object

Syntax	dbcc upgrade_object [ ( dbid dbname
	[, ['database.[owner].]compiled_object_name'
	'check' 'default' 'procedure' 'rule'
	'trigger' 'view'
	[, 'force' ] ] ) ]
	where:

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