For example, attribute syntaxes determine whether an attribute stores an integer, string, or stream data. The syntax also defines the matching rules that control the type of compare operations you can perform on the attribute value. You can't extend the schema by creating new attribute syntaxes. You must select your attribute's syntax from the set of predefined attribute syntaxes. This means that you can't assign a new data type or create an attribute that requires a data type not already defined by the NDS schema.
Attribute constraints are flags containing restrictions that affect an attribute value.
They can also impose constraints on NDS and NDS client operations. Attributes constraints specify whether the attribute Allows only a single value or multiple values. Has a range or size limit to the value. Is synchronized immediately, at the next scheduled interval, or never. Is hidden or viewable.