问题
Does SQL Server 2008 support the CREATE ASSERTION
syntax?
I haven't been able to find a straight answer on this.
回答1:
No SQL Server 2008 does not support this syntax.
回答2:
No, you'd use a CHECK constraint or a TRIGGER instead, depending on complexity.
- CHECK constraint: at the row level only
- TRIGGER: across rows or using other tables
回答3:
SQL Server 2008 does not support CREATE ASSERTION
.
In fact, no current SQL products support CREATE ASSERTION
properly. Sybase SQL Anywhere supports it but reportedly has problems allowing constraints to sometimes be violated. Rdb did support it when it was looked after by DEC (who apparently were influential in the early days of the SQL standards, probably the reason why CREATE ASSERTION
is in the standard in the first place) but that product is no more.
STOP PRESS: according to their documentation, HyperSQL (HSQLDB) supports assertions (though I'm left wondering why they don't shout about it on their list of features).
来源:https://stackoverflow.com/questions/4130039/does-sql-server-2008-support-the-create-assertion-syntax