DBCC
CHECKCONSTRAINS: Verify foreign key integrity
There
are two scenarios in SQL Server that can leave tables with rows that are not
bound by an existing FOREIGN KEY constraint or CHECK constraint:
- Newly added constraints ignore existing
table data if created using "WITH NOCHECK".
- Re-enabled constraints ignore all table updates and inserts that took
place since the constraint was disabled (disabled constraints appear with a
red icon in Teratrax
Database Manager. Right-click on constraint name to enable it).
Use DBCC
CHECKCONSTRAINS to check the integrity of your FOREIGN KEY constraints and CHECK
constraints and make sure there are no constraint violations. The command
returns a list of rows containing all violations. DBCC CHECKCONSTRAINTS does not
return any rows if there are no constraint violations.
Syntax
To check all constraints in the current database:
DBCC CHECKCONSTRAINTS
To check all constraints on a single table:
DBCC CHECKCONSTRAINTS ('table1')
You can run this sql command from the SQL window in Teratrax Database Manager.
By default, DBCC CHECKCONSTRAINTS returns the first 200 rows only.
DBCC CHECKCONSTRAINTS checks against enabled constraints only unless WITH
ALL_CONSTRAINTS is specified. The returned result consists of table name,
constraint name and a WHERE clause that identifies the violating row in the table.
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