How do I view constraints in SQL Server?

How do I view constraints in SQL Server?

Using SQL Server Management Studio

1. In the Object Explorer, right-click the table containing the check constraint and select Design.
2. On the Table Designer menu, click Check Constraints….
3. In the Check Constraints dialog box, under Selected Check Constraint, select the constraint you wish to edit.

What is the check constraint in SQL?

The CHECK constraint is used to limit the value range that can be placed in a column. If you define a CHECK constraint on a column it will allow only certain values for this column. If you define a CHECK constraint on a table it can limit the values in certain columns based on values in other columns in the row.

How do I find unique constraints in SQL Server?

Use sys. indexes, join the table, schema, object, and as an added bonus, you get not only unique constraints, but also unique indices, including filter.

How do I turn off check constraints?

To disable a check constraint for INSERT and UPDATE statements

1. In Object Explorer, expand the table with the constraint and then expand the Constraints folder.
2. Right-click the constraint and select Modify.
3. In the grid under Table Designer, click Enforce For INSERTs And UPDATEs and select No from the drop-down menu.

How do I find constraints on a database?

select table_name from user_constraints where (r_constraint_name) in ( select constraint_name from user_constraints where table_name = ‘T’ and constraint_type in ( ‘P’, ‘U’ ) ); So, we can easily find all the constraints on the table in oracle using data dictionary views.

Why do we use check constraint?

Check constraints are used to ensure the validity of data in a database and to provide data integrity. If they are used at the database level, applications that use the database will not be able to add invalid data or modify valid data so the data becomes invalid, even if the application itself accepts invalid data.

How do I turn off constraints in SQL?

To disable a foreign key constraint for INSERT and UPDATE statements

1. In Object Explorer, expand the table with the constraint and then expand the Keys folder.
2. Right-click the constraint and select Modify.
3. In the grid under Table Designer, select Enforce Foreign Key Constraint and select No from the drop-down menu.

How do I drop a constraint in SQL Server?

The SQL syntax to remove a constraint from a table is,

1. ALTER TABLE “table_name” DROP [CONSTRAINT|INDEX] “CONSTRAINT_NAME”;
2. ALTER TABLE Customer DROP INDEX Con_First;
3. ALTER TABLE Customer DROP CONSTRAINT Con_First;
4. ALTER TABLE Customer DROP CONSTRAINT Con_First;

What are SQL Server constraints?

Constraints in SQL Server are rules and restrictions applied on a column or a table such that unwanted data can’t be inserted into tables. This ensures the accuracy and reliability of the data in the database. Constraints maintain the data integrity and accuracy in the table.