The syntax of create default is:
create default [owner.]default_name as constant_expression
Default names must follow the rules for identifiers. You can create a default in the current database only.
Within a database, default names must be unique for each user. For example, you cannot create two defaults called phonedflt. However, as “guest,” you can create a phonedflt even if dbo.phonedflt already exists because the owner name makes each one distinct.
Another example: suppose you want to create a default value of “Oakland” that can be used with the city column of friends_etc and possibly with other columns or user datatypes. To create the default, enter:
create default citydflt as "Oakland"
As you continue to follow this example, you can use any city name that works for the people you are going to enter in your personal table.
Enclose character and date constants in quotes; money, integer, and floating point constants do not require them. Binary data must be preceded by “0x”, and money data should be preceded by a dollar sign ($), or whatever monetary sign is the logical default currency for the area where you are working. The default value must be compatible with the datatype of the column. You cannot use “none,” for example, as a default for a numeric column, but 0 is appropriate.
If you specify NOT NULL when you create a column and do not associate a default with it, Adaptive Server produces an error message whenever anyone fails to make an entry in that column.
Usually, you enter default values when you create a table. However, during a session in which you want to enter many rows having the same values in one or more columns, it may be convenient to create a default tailored to that session before you begin.
You cannot issue create table with
a declarative default and then insert data into the table in the
same batch or procedure. Either separate the create and insert statements
into two different batches or procedures, or use execute to perform
the actions separately.
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