Creating a Column Check Constraint

A column check constraint enforces a specified condition on a column. Add a column check constraint to a table using the Create Constraint Wizard.

Prerequisites

Database Version	Table Constraint Privileges
SAP Sybase IQ 15.3 and 15.4	You must have one of: DBA authority ALTER permission on the underlying table You own the underlying table
SAP Sybase IQ 16.0	You must have one of: ALTER ANY OBJECT system privilege ALTER ANY TABLE system privilege You have ALTER permission on the underlying table You own the underlying table

Task

In the Perspective Resources view, select the resource, and select Resource > Administration Console.
In the left pane, expand IQ Servers > Schema Objects > Tables, and then select Tables or Global Temporary Tables.
Select a table from the right pane and either:
- Click the arrow to the right of the name and select Properties, or
- From the Administration Console menu bar, select Resource > Properties.
The Table or Global Temporary Table Properties view appears.
Select Constraints.
Click New.
The Create Constraint Wizard appears.
On the Welcome page, select Column check constraint from the drop-down list. Click Next.

On the Constraint Name page, specify:

Option	Description
What do you want to name the new column check constraint?	Specify a descriptive name for the column check constraint.
For which column do you want to create the new check constraint?	Filter the Name, Primary Key, Data Type, Size, and Scale columns to locate the desired column. Select a single column you want to create the constraint on.

Click Next.
On the Definition page, specify the SQL definition of the check constraint and click Next. Use this example as a model when specifying a definition:
This example adds a constraint on the Employees table to ensure that the TerminationDate is always later than, or equal to, the StartDate.
```
CHECK(TerminationDate >= StartDate);
```
Click Finish to close the Create Constraint Wizard.
The Properties view appears.
Tip: Although you closed the Create Constraint Wizard, the constraint creation process is not complete until you click Apply and OK on the Table Properties view.
Do one of:
- Click OK to update any changes to the database and exit the properties view.
- Click Apply to update any changes to the database, but remain in the properties view.
- Click Cancel to cancel any changes not updated to the database and exit the properties view.