systypes

Provides information about all system and user-defined data types available in the database.

Name	Datatype	Description
uid	int	The user ID of a datatype creator.
usertype	smallint	The ID of a user-defined type.
variable	bit	The datatype lengh. The possible values are: 1 – A variable-length datatype. 0 – A fixed-length datatype.
allownulls	bit	Specifies whether NULL values are allowed for the datatype.
type	tinyint	The physical storage datatype used internally.
length	int	The physical length of the datatype in bytes.
tdefault	int	The object ID of the system procedure that generates the default value for the datatype.
domain	int	The object ID of the system procedure that enforces integrity checks for the datatype.
name	varchar(255)	The datatype name.
printfmt	varchar(255) null	Reserved for future use or formatting.
prec	tinyint null	The number of significant digits for numeric datatypes.
scale	tinyint null	The number of digits to the right of the decimal point.
ident	tinyint null	Specifies whether the column has the IDENTITY property. The possible values are: 1 – An IDENTITY column. 0 – A non-IDENTITY column.
hierarchy	tinyint null	The datatype precedence in mixed-mode arithmetic operations.
xtypeid	int null	The internal class ID for the datatype.
xdbid	int null	The database ID where the class is installed. The possible values are: -1 – A system database. -2 – The current database.
accessrule	int null	The object ID of the access rule in sysprocedures that applies to the datatype.