systypes (all databases)

Contains one row for each system-supplied and each user-defined datatype. Domains (defined by rules) and defaults are given if they exist. The rows that describe system-supplied datatypes cannot be altered. The system-supplied datatypes and their ID numbers (the contents of the name and type fields, respectively) are as follows:

Column Datatype Description
uid smallint User ID of datatype creator.
usertype smallint User type ID.
variable bit Variable-length datatype is 1, otherwise, 0.
allownulls bit Indicates the default nullability for this datatype. If nullability is specified with the CREATE or ALTER TABLE statement then that value will override the default nullability for this datatype.
type tinyint Physical storage datatype.
length tinyint Physical length of datatype.
tdefault int ID of stored procedure that generates default for this datatype.
domain int ID of stored procedure that contains integrity checks for this datatype.
name varchar(30) Datatype name.
printfmt varchar(255) Reserved.
prec tinyint Level of precision for this datatype.
scale tinyint Scale for this datatype. Scale is based on precision.

Index

systypes clustered, unique on name

ncsystypes nonclustered, unique on usertype

Referenced by Stored Procedures

sp_addtype sp_droptype sp_special_columns
sp_bindefault sp_dropuser sp_sproc_columns
sp_bindrule sp_help sp_unbindefault
sp_columns sp_rename sp_unbindrule
sp_datatype_info