As part of very
basic TSQL interview Question in interview
A default
constraint is associated with a particular attribute. It is an expression that
is used asthe default value when an explicit value is not specified for the attribute when you insert a row.
For example, the following code defines a default constraint for the orderts attribute in table
name order.
(representing the
order’s time stamp):
ADD CONSTRAINT
DFT_Orders_orderts
DEFAULT(SYSDATETIME())
FOR orderts;
The default
expression invokes the SYSDATETIME function, which returns the current
date and
time value. After
this default expression is defined, whenever you insert a row in the Orderstable and do not explicitly specify a value in the orderts attribute, SQL Server will set the
attribute value to SYSDATETIME.
Run clean up code DROP TABLE dbo.Orders, dbo.Employees;
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