The following table shows the contents of the SYSCOLUMNS system table.
SYSCOLUMNS system table
For each column in the SYSCOLUMNS system table, this table provides its data type, its length in bytes, whether it is nullable, and a description of its contents.
Column Name
Type
Length
Nullable
Contents
REFERENCEID
CHAR
36
false
Identifier for table (join with
SYSTABLES.TABLEID)
COLUMNNAME
VARCHAR
128
false
Column or parameter name
COLUMNNUMBER
INT
10
false
The position of the column within the table
COLUMNDATATYPE
org.apache.derby.
catalog.
TypeDescriptor This class
is not part of the public API.
2,147,483,647
false
System type that describes precision, length, scale, nullability,
type name, and storage type of data. For a user-defined type, this column can
hold a TypeDescriptor that refers to the appropriate type alias in
SYS.SYSALIASES.
COLUMNDEFAULT
java.io.Serializable
2,147,483,647
true
For tables, describes default value of the column. The
toString() method on the object stored in the table returns the text of
the default value as specified in the CREATE TABLE or ALTER TABLE
statement.
COLUMNDEFAULTID
CHAR
36
true
Unique identifier for the default value
AUTOINCREMENTVALUE
BIGINT
20
true
What the next value for column will be, if the column is
an identity column (Release 10.10 or earlier only)
AUTOINCREMENTSTART
BIGINT
20
true
Initial value of column (if specified), if it is an identity
column
AUTOINCREMENTINC
BIGINT
20
true
Amount column value is automatically incremented (if
specified), if the column is an identity column
The AUTOINCREMENTVALUE column has no meaning in a database that has been
fully upgraded to
Release 10.11 or higher. At Release 10.11 or higher, use the
to observe the next value for an
identity column.